| Subject | Date Asked |
| Physics | 2/11/2012 |
| Q: A 2075-kg elevator moves with an upward acceleration of 1.5 m/s^2. What is the tension in the cable ... A: Applying Newton's 2nd Law there is an upward force caused by the tension in the rope Ft and a ... | |
| hockey player questions | 2/6/2012 |
| Q: If two hockey pucks, one 4oz and the other one 6oz, are pushed on ice with the same force, which one ... A: The hockey puck with the greater mass will undergo the smaller acceleration and will, therefore, ... | |
| expansion of liquids | 2/6/2012 |
| Q: would it be possible to make mercury thermometre for measuring temperature if expansion of glass is ... A: Sure you could! But if the thermal expansion of the glass was greater than the thermal expansion of ... | |
| physics | 2/3/2012 |
| Q: The mass of 1 cubic meter of air at sea level is about 1.3kg. How much does it weight in newtons? ... A: To convert the mass in kilograms to force in Newtons multiply by 9.8 N/kg. Multiply by 8000 to find ... | |
| Mass energy | 2/3/2012 |
| Q: Where does the idea come from that energy is "within" mass, when Einstein's equation plainly ... A: That is not what Einstein's equation says! E=m*c^2 says that when you convert mass into energy (as ... | |
| reflected light | 2/1/2012 |
| Q: Does reflected light say from the moon have an intensity registered in say candelpower? or lumens? A: I do not know the actual brightness of the reflected light from the sun but I do know that it is ... | |
| Physics | 1/30/2012 |
| Q: I have a wire, that carry a current I? Can we apply the Ampere's law from Maxwell's equation to this ... A: You only need to worry about current density if you are looking for,the magnetic field WITHIN the ... | |
| network of circuits | 1/27/2012 |
| Q: I want to ask some problems about network in circuits. I am required to find the initial current ... A: Immediately after the switch has been closed no charge has yet accumulated on the plates of the ... | |
| energy stored in capacitor | 1/21/2012 |
| Q: CASE 1: When dielectric is inserted between plates of capacitor<e increases>, which is disconnected ... A: Case 1: Adding the dielectric weakens the electric field between the plates. As a result the ... | |
| Physics help | 1/14/2012 |
| Q: my name is Garettruben. I am new member here.So I would like to ask you help on this question.I'm ... A: One of the fundamentally conserved quantities in the universe is angular momentum. In order to ... | |
| physics | 1/11/2012 |
| Q: I am doing my science fair project on "balloon powered rocket car" for this i wanted to know if my ... A: This problem can be looked at in two different ways: momentum conservation and energy conservation. ... | |
| physics | 1/11/2012 |
| Q: I am doing science fair project on "skewer through a balloon" . I made my problem for this project ... A: I think that the balloon is much less likely to pop if you put the skewer through the balloon where ... | |
| changes of energy stored in capacitor when there is insertion of dielectric in between the parallel plates | 1/10/2012 |
| Q: I am studying the changes of electrical potential energy stored in parallel-plate capacitor when ... A: Case 1: Since the introduction of the dielectric reduces the electric field between the parallel ... | |
| Music Teacher has Vibration Question | 1/9/2012 |
| Q: When playing my Boombox, a tissue happened to be vibrating in front of it. This was not surprising, ... A: Sound is a longitudinal [lengthwise] compression wave and consists of alternating areas of high ... | |
| physics | 1/8/2012 |
| Q: A ROPE IS ATTACHED IN 100LB OBJECT AND IS PULLED UPWARD WITH A FORCE OF 150LB.WHAT IS THE UPWARD ... A: Since the upward force is 50 pounds more that the weight of the mass,, the mass will accelerate ... | |
| Surface area and friction | 1/6/2012 |
| Q: I am studying physics and i am doing a project for an assignment. Essentially i made an attwood ... A: Without actually doing the experiment with you I cannot account forthe results. When Ihave done ... | |
| sonic energy | 1/3/2012 |
| Q: I would like to make a device that is able to create enough sonic energy to vibrate a plant is this ... A: I would use an "open tube" with a resonant frequency that matches the frequency of the sound you ... | |
| electrostatically charged spheres | 12/29/2011 |
| Q: please tell me; does it make a difference to the output voltage if two or more electrostatically ... A: It only matters if the potentials of the spheres are different. If the two spheres are at the same ... | |
| Physics | 12/23/2011 |
| Q: This is a most intriguing question that i have asked many people and got different answers. Could ... A: An object at the center of the Earth would feel no "weight" as a result of the Earth's gravitational ... | |
| particle physics | 12/22/2011 |
| Q: " A particle cannot spontaneously decay into particles heavier than itself is actually a consequence ... A: Yes, in fact that is the whole point ofthe Large Hadron Collider! We give protons a LOT of energy ... | |
| centripetal force | 12/21/2011 |
| Q: Sir I am confused that why in death well(a person motorcycling on slightly curved vertical walls)the ... A: The fundamental problem here is that your understanding of the force of friction is that it does NOT ... | |
| Science Project Bigger Wheels Faster? | 12/18/2011 |
| Q: I am helping my son with his 4th grade science project and need some help. His project has to deal ... A: All things being equal the smaller wheeled vehicle should have the greater acceleration since less ... | |
| Physics | 12/17/2011 |
| Q: James A 40 kg block on a frictionless table is connected to a 15 kg mass by a string passing over ... A: According to Newton's 2nd Law the sum of the forces in the direction of the acceleration is equal to ... | |
| about motion | 12/17/2011 |
| Q: 1.A person walking on the road with load on his head does not do work against gravity. 2.A body at ... A: 1. As you walk horizontally there is no net change in vertical position of the load and so no NET ... | |
| Electrical PE stored in capacitor | 12/16/2011 |
| Q: I am VERY CONFUSED with the Electrical PE stored in capacitor. It is what I am thinking about… (A) ... A: The problem here is that you are confusing average potential difference and instantaneous potential ... | |
| Coefficients | 12/14/2011 |
| Q: Do you know the coefficient of felt on plastic? A: Not off the top of my head but it is easy enough to find out. I just used a spring scale to pull a ... | |
| charges on a parallel-plate capacitor | 12/8/2011 |
| Q: The two plates of a parallel-plate capacitor initially carry equal amounts of positive charges. If ... A: The equation E=2*pi*k*sigma predicts the electric field E near a planar distribution of charge where ... | |
| mass | 12/7/2011 |
| Q: why is it that mass of a body can never be negative? A: We don't really know. In an experiment reported last year scientists measured the acceleration of ... | |
| charges on a parallel-plate capacitor | 12/6/2011 |
| Q: The two plates of a parallel-plate capacitor initially carry equal amounts of positive charges. If ... A: The electric field E between the two plates of a capacitor is equal to the sum of the electric ... | |
| Mass | 12/5/2011 |
| Q: What is a mass(confused with definition of mass)? How it is measured? Is there any special apparatus ... A: Mass is a measure of matter which consists primarily of how difficult it is to change the mass's ... | |
| Astophysics | 12/4/2011 |
| Q: What is different about today's asteroid belt and kuper belt from the early condition of the solar ... A: There were, of course, MANY more such objects in the early universe. Over time the vast majority of ... | |
| Phyics | 12/4/2011 |
| Q: A 2.9 × 10 3 kg car accelerates from rest at the top of a driveway that is sloped at an angle of ... A: Using energy conservation: The total energy TE1 at the top of the incline will be only ... | |
| velocity calculation | 11/29/2011 |
| Q: Sir I am a bit confused in this question and would be very much thankful to you if you answer this ... A: Kinetic energy is the ability of an object to do work because the object has a velocity. In this ... | |
| I need help with the "sources of error" part of this pendulum lab | 11/29/2011 |
| Q: We performed a lab involving a pendulum in which we were to find the relationship between the period ... A: What about errors related to: 1) The small angle approximation - if you pull the pendulum back more ... | |
| speed calculation | 11/28/2011 |
| Q: Sir I would be very much thankful to you if you could answer this question.Please explain it a bit ... A: All one dimensional kinematics problems can be solved in the same way. Since there are two available ... | |
| centripetal force | 11/27/2011 |
| Q: how does centripetal force depend on velocity? what happens when the velocity increases? A: Centripetal force depends on the centripetal acceleration which is ac=v^2/R and is equal to: ... | |
| Dark Matter | 11/22/2011 |
| Q: I heard that dark matter was a result of seeing all the gazillion kgs of mass in the universe and ... A: Dark matter has been hypothesized due to very real measurements made regarding the motion of stars ... | |
| instantaneous action | 11/21/2011 |
| Q: Kolvacin, Is there such a thing as an instantaneous action in the universe? Not instantaneous ... A: As far as we know NOTHING, including information, can travel faster than the speed of light. We have ... | |
| Archery and Shooting Games. | 11/20/2011 |
| Q: http://en.wikipedia.org/wiki/Archery http://en.wikipedia.org/wiki/Archery_at_the_Summer_Olympics ... A: A projectile flying through the air will also be conserving energy [if we neglect the effects of air ... | |
| Elastic Collision | 11/16/2011 |
| Q: A 640 g ball strikes a wall at 15.1 m/s and rebounds at 13.9 m/s. The ball is in contact with the ... A: According to Newton's 2nd Law: F=m*a. [Where F is the sum of the forces acting on the system.] ... | |
| nonuniform circular motion | 11/15/2011 |
| Q: I am having some difficulty getting the answer. Thank you! A tetherball is a 0.56kg soccer size ball ... A: Since this ball is moving in a circular path it is accelerating centripetally and so Newton's 2nd ... | |
| convex lens | 11/9/2011 |
| Q: respected sir, can you please tell me what are the uses of convex mirror in detail?please sir it ... A: Convex mirrors produce erect virtual images which can be significantly smaller than the 1:1 ... | |
| physic | 11/7/2011 |
| Q: sir my question is that,does dilation means in special theory of ralativity that time really passes ... A: I guess it all depends by what you mean by "time really passes more slowly". If you mean will the ... | |
| Rotating objects | 11/7/2011 |
| Q: A pulsar is a rapidly rotating neutron star that emits a radio beam the way a lighthouse emits a ... A: Since the current period of the star is To=0.0731s and since the period increases by dT=2.16 x 10^-6 ... | |
| (REVISED!)Electric field strength VS Density of equipotential lines | 11/6/2011 |
| Q: Is electric field strength =density of equipotential lines? Below is what I’m thinking about. ... A: You are essentially correct. The direction of the electric field is in the direction of the greatest ... | |
| Question about electric field | 11/4/2011 |
| Q: X and Y are two different points in an electric field. A small charged object is released from rest ... A: You are on the right track, but you are not quite there yet. To predict the path you need to first ... | |
| Question about electric field | 11/4/2011 |
| Q: X and Y are two different points in an electric field. A small charged object is released from rest ... A: If the particle is SLOWLY moving it could, in principle, come close to following the electric field ... | |
| momentum and collisions | 11/3/2011 |
| Q: a 2.1 kg brick is placed gently upon a 2.9 cart originally moving with a speed of 26 cm/s determine ... A: The solution of any two body, one dimensional collision will be of the form: m1*v1+m2*v2=m1*v3+m2*v4 ... | |
| Thermodynamis | 11/1/2011 |
| Q: Here's the main part of theA 180g copper bowl contains 170g of water, both at 25 degrees Celsius. A ... A: The heat lost of gained by a system is calculated using: dQ=m*c*dT where dQ is the heat lost of ... | |
| Question about electric field | 11/1/2011 |
| Q: X and Y are two different points in an electric field. A small charged object is released from rest ... A: The problem here is that you are assuming that the electric field lines describe the PATH of the ... | |
| atomic physics | 10/31/2011 |
| Q: Why do most stable nuclei have equal number of protons and neutrons? A: If you look at the binding energy per nucleon, a measure of how tightly nucleons are held together ... | |
| physics | 10/29/2011 |
| Q: For q I am getting 19.8 and M I am getting -.06667, but they are wrong. A converging lens of focal ... A: When an object is placed in front of a lens the relationship among the position of the object p, the ... | |
| Useing water weight to increase boyancy | 10/24/2011 |
| Q: I am a special education teacher now living in Italy having moved from Texas five years ago. We are ... A: If the float has a volume of 1.0 cubic meters it will displace 1.0 cubic meters of water. Since ... | |
| oscillation | 10/23/2011 |
| Q: what is the difference between phase, phase constant and phase difference?? A: Assuming that you are referring to a typical simple harmonic wave or motion where: A=Ao*sin(theta) ... | |
| Mass Transfer | 10/20/2011 |
| Q: Assuming air to be composed O2 and N2, with their partial pressures in the ratio of 0.21:0.79, what ... A: Since oxygen O2 has a molecular mass of 32g/mole while nitrogen is 28g/mole the mass fractions of ... | |
| Levitating a ball/ring | 10/19/2011 |
| Q: I trying to make a device that can levitate a small ball /bracelet size ring in a big transparent ... A: 1) An electromagnet is certainly capable of producing a stronger magnetic field at a greater ... | |
| trajectory | 10/17/2011 |
| Q: A projectile shot with an initial velocity of 51 m/s at an angle of 45° follows a parabolic path and ... A: When you fire a projectile at an angle the first step is to break the initial velocity of the ... | |
| velocity | 10/17/2011 |
| Q: I was hoping if you could help me out with this problem: A toy car goes 10.3 meters in 4.15 seconds ... A: If the toy car goes 10.3m in 4.15s its average velocity will be: V1=D/t=10.3m/4.15s=2.48m/s The fact ... | |
| Levitating a ball/ring | 10/14/2011 |
| Q: I trying to make a device that can levitate a small ball /bracelet size ring in a big transparent ... A: 1) To levitate higher you will need a correspondingly stronger magnetic field. Producing such a ... | |
| molecular physics | 10/11/2011 |
| Q: In case of laser action if the both stimulated absorption and stimulated emission have equal number ... A: If the rate at which energy enters the system is identical ti the rate at which energy leaves the ... | |
| centripetal force | 10/10/2011 |
| Q: what is origin of centripetal force which keeps the body in circular path? A: The first thing to keep in mind is that "centripetal force" does NOT exit on it's own! Centripetal ... | |
| question | 10/9/2011 |
| Q: a block of mass m is pulled by a constant power P placed on a rough horizontal plane. then friction ... A: Instantaneous power P is equal to the product of the force being applied F and the instantaneous ... | |
| centre of mass | 10/8/2011 |
| Q: Sir I just want to know how to find centre of mass of any rigid body.plzzz give an algorithm or step ... A: To find the x coordinate of the center of mass of any system of objects you multiply the mass of ... | |
| Echo - Reflection of Sound | 10/7/2011 |
| Q: http://en.wikipedia.org/wiki/Echo_%28phenomenon%29 1. why echo only in specific places/areas ? - ... A: 1. The existence of an echo depends upon there being an appropriate reflecting surface. What, ... | |
| equilibrium | 10/5/2011 |
| Q: Why do high heels worn by a lady walking on a wooden floor leave impressions on the floor? Why do ... A: 1. It is not so much that the heels are "high" but because their floor contact area is so small. ... | |
| Physics | 10/5/2011 |
| Q: If a washing machine's drum has a radius of 21 cm and spins at 3.9 rev/s, what is the strength of ... A: For something moving in a circular path the acceleration is centripetal and is given by a=v^2/R. In ... | |
| Electric potential | 10/4/2011 |
| Q: Give examples of situations in which the potential of a charge body has a sign opposite to that of ... A: 1. If a positive charge is located close to a negatively charged body it will have negative ... | |
| Light | 10/3/2011 |
| Q: I am an Italian boy who has been studying areas of the humanities -like history, linguistics ... A: Yes, the color of light is determined by the energy content of the light. Larger transitions ... | |
| Waves | 10/2/2011 |
| Q: I'm a first year physics student and I'm having a lot of difficulty with my physics homework. I'm ... A: The first thing you to know is what each of the variables in the equation represent: k [measured in ... | |
| Optics | 10/2/2011 |
| Q: Im studying in 12th. I want to know the reason for the early sunrise and late sunset? A: Because the Earth is tilted at a 23 degree angle relative to the sun [the ecliptic] when the ... | |
| Light | 9/30/2011 |
| Q: I am an Italian boy who has been studying areas of the humanities -like history, linguistics ... A: You are correct! The diffusion and scattering of light is due to multiple electron transitions as ... | |
| Gauss ratings | 9/27/2011 |
| Q: I'm trying to figure out what kind of magnet I have here; it feels quite strong compared to bar ... A: The magnetic field at the surface of the magnet is determined primarily by the materials from which ... | |
| potentially world changing theory | 9/25/2011 |
| Q: I'm not sure how to describe this in the subject box, it's such a weird idea that even though I ... A: The fact is that we cand and DO transmutate one atom into another all the time! But that is not the ... | |
| Ap physics B | 9/24/2011 |
| Q: A ball is thrown horizontally from the top of a building 110 m high. The ball strikes the ground 71 ... A: All 2 dimensional kinematics problems can be done in the same way. There are 6 kinematics variables ... | |
| Einstein's theory of special relativity. | 9/23/2011 |
| Q: There was a man on the planet earth, and there was a man in a space vessel and he travelled for 70 ... A: The issue is that the astronaut CHANGED reference frames and, therefore, briefly moved outside the ... | |
| Standing wave in an open end air column | 9/22/2011 |
| Q: I am confused about how is it possible for a standing wave to be formed in an open end air column? ... A: Waves are being reflected due to the impedance mismatch between the air confined by the walls of the ... | |
| Physics Help | 9/21/2011 |
| Q: Unless I receive an answer to this within the next three hours (in which case, kudos to you) my ... A: I wouldn't do it that way at all! Much easier would to be to use energy conservation. After giving ... | |
| I Want A simple Title in physics to make a research on | 9/20/2011 |
| Q: I Want A simple Title in physics to make a research on im a student and the Auc(American University ... A: There are many possibilities here. Are you going to just write about theory or are you going to ... | |
| Solve please | 9/19/2011 |
| Q: 1)A ship is sinking in the dark ,the sailors on the ship fire a distress flare into air.it explodes ... A: For all practical purposes the light from the explosion reaches you instantaneously [light travels ... | |
| Scalars and Vectors - Examples | 9/18/2011 |
| Q: http://en.wikipedia.org/wiki/Scalar_%28physics%29 Scalars are physical quantities which have ... A: A vector quantity will be any quantity which REQUIRES direction for the quantity to make sense. So ... | |
| Gauss' law | 9/16/2011 |
| Q: Suppose that a Gaussian surface enclose no net charge. Does Gauss' law require that electric field ... A: If you apply Gauss' Law to a long linear charge density L the relevant Gaussian surface would be a ... | |
| Gauss' law | 9/15/2011 |
| Q: Suppose that a Gaussian surface enclose no net charge. Does Gauss' law require that electric field ... A: 1) Not at all! All Gauss' Law implies is that the NET electric flux through a closed surface ... | |
| Physics | 9/14/2011 |
| Q: A plane flies at a velocity of 500 kilometers per hour 35 degrees North of East for 90 minutes then ... A: If the plane first flies at 500km/hr of 90min [1.5hr] the plane's final displacement at the end of ... | |
| physics | 9/13/2011 |
| Q: A chain that can support 2000 N is suspended between two trees. a 200 kg motor hangs from the ... A: This a Newton's 1st Law problem with 3 concurrent forces acting on a point [the location where the ... | |
| average velocity | 9/12/2011 |
| Q: A bus travels 250 km south along a straight path with an average velocity of 81 km/h to the south. ... A: Since D=Vave*t the time for the first leg would be: t1=D/V=250km/81km/hr=3.10hr Then the rest stop: ... | |
| physics | 9/11/2011 |
| Q: 1. State Fleming's left-hand rule. 2. What is the principle of an electric motor? 3. What is the ... A: 1. See http://en.wikipedia.org/wiki/Fleming's_left-hand_rule_for_motors for a thorough description! ... | |
| Vectors and Vector Addition | 9/9/2011 |
| Q: a vector A has a magnitude of 40.0 m and ponts in a direction of 20.0 degrees below the positive x ... A: The first step will be to break each vector up into its x and y components: For vector A: ... | |
| Matter | 9/9/2011 |
| Q: I have recently been getting really into physics lately and very interested in how the universe ... A: Atoms are held together in matter by the electromagnetic force between charged particles. The shape ... | |
| Reaction and effect | 9/8/2011 |
| Q: There are theories on the effects of an asteroid strike on the earth. My question is what would the ... A: The size, the direction and the speed of the asteroid/asteroids all matter! Why the issue of 2 ... | |
| Electric field | 9/7/2011 |
| Q: Sir, I would like ask three questions. 1. A point charge is moving in an electric field at ... A: 1. Of course! The equation predicting the force on a charged particle in an electric field is F=E*q ... | |
| double slit experiment | 8/14/2011 |
| Q: ANSWER: When a beam of electrons is put through a double slit an interference pattern is formed ... A: I don't know WHY it happens and neither does anyone else! This is the problem with quantum theory. ... | |
| double slit experiment | 8/14/2011 |
| Q: ANSWER: When a beam of electrons is put through a double slit an interference pattern is formed ... A: From a physicist's point of view what exists is what we measure. For example, there is NO direct ... | |
| double slit experiment | 8/11/2011 |
| Q: hi james can you tell me why the double slit experiment changes if you look at it???? A: When a beam of electrons is put through a double slit an interference pattern is formed according ... | |
| EMF | 8/10/2011 |
| Q: I live about 300 feet away from hi power lines. I recently bought a gauss meter (dr.gauss name) to ... A: A Gauss meter is designed to measure magnetic field strength. The background magnetic field is on ... | |
| electric fields | 8/3/2011 |
| Q: i ben trying to ansa this question 4 hours so cn u plz help.hear the''A proton travels in the x ... A: As the proton enters the electric field directed perpendicularly to the initial direction of motion ... | |
| Physics | 8/1/2011 |
| Q: kevin and jonas are carrying nick on a uniform horizontal board 3.0m long which weighs 200N. nick ... A: This is a typical torque problem. [Remember that torque is equal to the product of the applied force ... | |
| Human Being Resistance Power. | 7/31/2011 |
| Q: Human Being Body is a Good Conductor of Electricity (consists of watery fluids) since Water is good ... A: Luck of the draw - nothing more. Death depends on what systems of the body are specifically affected ... | |
| Human Being Resistance Power. | 7/30/2011 |
| Q: Human Being Body is a Good Conductor of Electricity (consists of watery fluids) since Water is good ... A: Actually, pure water is a lousy conductor of electricity! Only when salts are added does the water ... | |
| physics | 7/27/2011 |
| Q: under what condition the magnitude of average velocity will be equal to average speed for a moving ... A: Average speed is defined to be: speed=distance/time While average velocity is defined to be: ... | |
| Magnetic force | 7/26/2011 |
| Q: I am currently studying MA Fashion in London. I am currently looking at magnets and how I can create ... A: Unfortunately, there is no reasonable way to do this. As far as is currently known this cannot be ... | |
| How efficiently different technologies turn heat energy into mechanical energy? | 7/25/2011 |
| Q: I would like to see a comparison of how efficiently different technologies turn heat energy into ... A: Whatever the technology, the thermal efficiency of a heat engine is determined by 2 distinct ... | |
| gravity/space | 7/25/2011 |
| Q: if you were to suddenly put a large object in space then the space would be pushed out to the ... A: No, because the addition of mass to a particular space doesn't push space out of the way but it does ... | |
| gravity/space | 7/24/2011 |
| Q: if you were to suddenly put a large object in space then the space would be pushed out to the ... A: The "space" is not pushed out of the way! Space is not like air - which can be displaced by an ... | |
| Physics, projectile motion and momentum | 7/24/2011 |
| Q: An arrow undergoing projectile motion passes through an apple while traveling at 45 degrees above ... A: Yes it can be used but more information is needed! For example you nee the mass of the arrow, the ... | |
| dark matter | 7/23/2011 |
| Q: what actually does dark matter do? does it really exist? A: Ordinarily you can determine the orbital velocity of an orbiting satellite by using Newton's 2nd ... | |
| curious | 7/20/2011 |
| Q: What is negative matter; is it the same as dark matter, & if not, what's the difference? ... A: Every piece of matter has a corresponding piece of antimatter. For example an electron has an ... | |
| Law of decay | 7/20/2011 |
| Q: A certain radioactive material is known to decay at a rate proportional to the amount present. A ... A: Because your problem statement indicates that the rate of decay dm/dt is directly proportional to ... | |
| time | 7/19/2011 |
| Q: it is said that once a particle approaches the speed of light the time eventually slows down for the ... A: How is that possible? I don't really know except to say that this is what the equations predict and ... | |
| tachyon | 7/19/2011 |
| Q: is there any proof for the existence of tachyon? as it travels faster than the speed of light are ... A: Sorry, but there is no evidence for the existence of tachyons. That does not, of course, mean that ... | |
| Heat Engine | 7/18/2011 |
| Q: A heat engine has the three step cycle shown above. Starting from point A, 1 L (liter) of ideal gas ... A: Since the process C - -> A is a compression [volume is decreasing] while pressure is increasing work ... | |
| Motion | 6/29/2011 |
| Q: Sir, why can't acceleration be equal to speed divided by time? Why it is velocity divided by time? ... A: Actually, depending on what you are looking for in a particular problem you can divide the change in ... | |
| Physics | 6/27/2011 |
| Q: A 50 kg woman stands at one end of a 25 kg, uniform, 20 m long board. How far from the woman is the ... A: First assume that the end of the board opposite the woman is the origin. The center of mass of the ... | |
| physics | 6/26/2011 |
| Q: Name the factors onwhich the strength of electric current flowing in a given conductor depends? A: The magnitude of the electrical current flowing through a wire depends on: 1) The magnitude of the ... | |
| physics | 6/23/2011 |
| Q: I am lost at how to approach this problem. A car can decelerate at -4.80 m/s^2 without skidding ... A: According to Newton's 2nd Law the sum of the external forces SF acting on an accelerating body is ... | |
| Physics | 6/22/2011 |
| Q: The engine of a train(length l)moving with uniform acceleration, passes an electric pole with a ... A: All kinematics problems involve 2 equations: Df=1/2*a*t^2+Vo*t+Do and Vf=a*t+Vo These two ... | |
| ELECTRICITY | 6/19/2011 |
| Q: IS POTENTIAL AT EVERY POINT ON A CONDUCTING WIRE SAME... PLEASE EXPLAIN CURRENT FLOWS THROUGH AN ... A: Yes and no! If you use a voltmeter on a typical wire all of your readings would be the same for all ... | |
| physics | 6/19/2011 |
| Q: A 1300kg car runs into the rear of a 1700-kg minivan that was moving at 5m/s. The two vehicles are ... A: In any two body collision problem the total momentum at the beginning will be equal to the total ... | |
| Speed and Distance of Travel | 6/17/2011 |
| Q: An automobile is traveling at 45 miles per hour and the traffic light changes requiring the vehicle ... A: All kinematics problems can be done in the same way! There are 6 possible kinematics variables and 2 ... | |
| Physics | 6/16/2011 |
| Q: A car is traveling at a steady speed of 90kph, the driver carries out an emergency stop, locking all ... A: First converting 90km/hr to m/s. Vo=90km/hr*1000m/km*1hr/3600s=25m/s C. horizontal surface For a dry ... | |
| error analysis | 6/15/2011 |
| Q: Sir I am doing the chapter error analysis in measurement. In that 1) one statement in given that the ... A: 1) Actually, I would consider 1/2 the least count to be the error limit of the measuring instrument ... | |
| Trigonometry | 6/14/2011 |
| Q: If a girl is 1.5m tall how long is her shadow (correct to one decimal point) when the angle of ... A: If the girl is 1.5m tall and elevation of the sun above the horizontal is 58 degrees, the girl's ... | |
| Kinetic Energy | 6/14/2011 |
| Q: A mass, weighing 70kg, falls vertically 100 meters. How much potential kinetic energy is ... A: Because total mechanical energy is conserved [remains the same] as long as there are no significant ... | |
| Physics | 6/13/2011 |
| Q: Calculate the centre of mass of a lamina in the shape of a quarter-circle with constant density and ... A: To find the x coordinate of the center of mass Xcm of a system of particles multiply the mass of ... | |
| Orbit | 6/13/2011 |
| Q: The fastest possible rate of rotation of a planet is that for which the gravitational force on ... A: For the given conditions to be true the centripetal acceleration [ac=v^2/R] at the equator would ... | |
| Dynamic Friction | 6/12/2011 |
| Q: A lorry is travelling at a steady speed of 50 km h−1 when an emergency occurs. The driver ... A: If the car is moving on a horizontal surface, the only force acting to accelerate the car will be ... | |
| physics | 6/10/2011 |
| Q: plz answer my question :consider a girl of mass 40 kg standing on a still board of mass 60 kg . ... A: Assuming that the board is floating and that the frictional force on the board is effectively zero, ... | |
| Simple Harmonic Motion | 6/10/2011 |
| Q: Greetings: Regarding your answer to ... A: As you displace the object to the right from equilibrium the spring on the left PULLS the object ... | |
| Projectiles on Building | 6/7/2011 |
| Q: A ball is thrown from the ground onto a roof of height yroof = 15 m from a distance of x = 7 meters ... A: Since the ball's reaches a point 4.0 meters high than the roof the maximum height of the ball, at ... | |
| Two-Dimensional Kinematics | 6/7/2011 |
| Q: The archerfish hunts by dislodging an unsuspecting insect from its resting place with a stream of ... A: For all kinematics problems there are 6 variables: Do,Df,Vo,Vf,A and t And 2 equations: ... | |
| Physics: electric currents, magnetic fields, ampere's law | 6/5/2011 |
| Q: Each of the ten turns of wire in a vertical, rectangular loop carries a current of 0.22 A. The loop ... A: The loop would slowly rotate until the normal to the loop is parallel to the magnetic field. In this ... | |
| force of hail balls hitting concrete | 6/5/2011 |
| Q: I would like to know how much force is applied to flat concrete at the moment of contact when a hail ... A: There are several issues here! 1. How fast is the hailstone moving when it collides with the ground? ... | |
| science project in physics- working model | 6/3/2011 |
| Q: I want to make a working model for my physics science project, can you suggest me some topics for my ... A: Sorry, but I think you are asking me for too much for a project. As a teacher the point of a project ... | |
| science project in physics- working model | 6/3/2011 |
| Q: I want to make a working model for my physics science project, can you suggest me some topics for my ... A: My best suggestion would be to make a "Rube Goldberg" machine. Rube Goldberg was a cartoonist who ... | |
| Physics | 6/1/2011 |
| Q: https://wug-s.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?cc/DuPage/Phys1201/fall-evening/ho ... A: The first leg of the football player's displacement is: A = 4m j [Any vector parallel to the ... | |
| Monumental Questions | 5/26/2011 |
| Q: If you have a golf ball falling to earth the earth pulls on it with force "A". The golf ball pulls ... A: 1. There is one thing that is special about the gravitational force Fg and that is that it depends ... | |
| Pendulums and Newtons | 5/25/2011 |
| Q: In our lab we determined that only the length of the pendulum affected the period. We found the ... A: Actually, a graph comparing the period of a pendulum and the length should NOT be a straight line! ... | |
| electricity : power | 5/22/2011 |
| Q: 1) A piece of wire of resistance 4 ohms is bent through 180 degree at its midpoint and the two ... A: The tree bulbs in parallel will be much brighter! Why? Because when you put the three bulbs in ... | |
| electricity : resistance | 5/21/2011 |
| Q: 1) A piece of wire of resistance 4 ohms is bent through 180 degree at its midpoint and the two ... A: Folding the wire cuts the length in half and doubles the cross section. Since resistance is ... | |
| Innovative idea | 5/20/2011 |
| Q: Sir, I am a deputy engineer in an organization, which i don't want to disclose. I just , after ... A: Any such device would contradict ALL understanding of the Laws of Thermodynamics and physics. The US ... | |
| string | 5/20/2011 |
| Q: If you pluck a string 1/3 from one end, which partials will be missing? Which partial is likely to ... A: The equation describing a standing wave is given by: A=Ao*sin(k*x)cos(w*t) where k=2*pi/y is the ... | |
| frequency | 5/19/2011 |
| Q: If the tension of a 350 Hz string is made third as large, what would the new fundamental frequency ... A: The speed of a wave in a string is given by: s=sqrt[T/mu] where T is the tension in the string and ... | |
| damping time and resonance curve | 5/19/2011 |
| Q: The drumhead of a kettledrum has a frequency of 75 Hz. The drumhead makes about 15 oscillations ... A: I agree with your damping time being 0.20seconds. As for the width of the resonance curve you don't ... | |
| charges | 5/18/2011 |
| Q: I have been studying physics but I just realized i do not know where chargers come from..why ... A: Where does charge come from? No one knows! Charge just exists as one of the fundamental properties ... | |
| string tension | 5/16/2011 |
| Q: tomorrow's my exam and I'm really worried. could you help me? I have two blocks attached to one ... A: This is a little difficult to answer accurately without some additional information, but let's make ... | |
| physics working model | 5/14/2011 |
| Q: sir i am studying in class 10. i have to make a working model related to physics.so please provide ... A: One of the most fun projects to make is a "Rube Goldberg" machine which can demonstrate many ... | |
| Springs | 5/13/2011 |
| Q: A ball of mass 2.6 kg, starting from rest, falls 55 cm directly down onto a vertical coiled spring, ... A: The easiest way to do this problem is to use energy conservation. Before the ball is dropped it has ... | |
| physics-simple harmonic motion | 5/10/2011 |
| Q: A certain spring has a frequency of 100Hz when a 50 g mass is hung from it. What would the frequency ... A: The frequency of a mass vibrating on the end of a spring is given by: f=1/2pi*sqrt[k/m] To find the ... | |
| Mathematics | 5/9/2011 |
| Q: Q. A railway train is moving on a circular curve of 1500m radius at the rate of 66kmph. Through what ... A: If the train is moving with a linear velocity v of: v=66km/hr=66,000m/3600s=18.2m/s the resulting ... | |
| Dual nature of photon | 5/8/2011 |
| Q: It is said that photon has a dual nature and while it propogates it is in wave nature.when the same ... A: Light contains energy and as such is affected by gravitational fields. Ordinarily this effect is ... | |
| photon | 5/7/2011 |
| Q: If photon does not have any charge,then why do we call it electromagnetic?Also when a photon ... A: We call light "electromagnetic" because light is made up of in phase sinusoidally oscillating ... | |
| electromagnetism | 5/5/2011 |
| Q: i need help explaining to me an experimental way i could proof electromagnetism in the lab. so, i ... A: The difficulty as I see it is the VERY short time allowed for measurements to take place. This will ... | |
| energy state | 5/4/2011 |
| Q: Can atoms undergo slight changes such as when bumping up against eachother without being considered ... A: Yes. Energy states are primarily the venue of particles confined in a particular area or space. For ... | |
| Question about the Chernobyl Disaster and Physics | 5/4/2011 |
| Q: I was wondering if there was a connection between the Chernobyl Disaster and any part of Physics as ... A: If you are going to write a detailed report you will need to thoroughly research the events ... | |
| physics | 5/1/2011 |
| Q: a body is moving in a straight line having the velocity v1 for the first half and v2 for the next ... A: If the moving body moved at velocity v1 for the first half t/2 and moved at a velocity of v2 for the ... | |
| Physics - Rotational Motion | 4/30/2011 |
| Q: Hey James, how are you? I just have a question to ask here as follows; A solid disk is rolling ... A: A rolling disk contains both linear and angular kinetic energy. Therefore, the total energy of a ... | |
| physics | 4/30/2011 |
| Q: I would like to clarify this question A tin weighs 5 N when empty and 70 N when completely full of ... A: Density p is equal to the ratio of mass m to volume V: p=m/V In this case the weight W of the paint ... | |
| Physics | 4/28/2011 |
| Q: I teach 6th grade language arts. Today, we watched "Journey to the Center of the Earth" (the one ... A: Since the acceleration of gravity the velocity of the glow stick at the end of 3 seconds will be: ... | |
| Energy needed to tip over versus energy needed to tip back up again | 4/28/2011 |
| Q: Imagine a MagLIGHT brand flashlight... http://bit.ly/hcxlyI ...which has its batteries in its long ... A: Let's make several assumptions for an example calculation: 1. The mass of the flashlight is m=2.0kg ... | |
| equal weights on the scales | 4/26/2011 |
| Q: why when we put equal weights on the scales it swings up and down for some time till it comes to ... A: It swings up and down because the system is an equilibrium system [opposite forces/torques are ... | |
| Physics | 4/26/2011 |
| Q: hope that you are fine & enjoying your life with a good health, i have a question for you sir, what ... A: The deterministic approach assumes that every result has a specific cause which leads to that ... | |
| Magnetism | 4/24/2011 |
| Q: Q1)I've tried to find B(Magnetic Field)at the centre of a current carrying ring in two ways(Please ... A: Ampere's Law states that the integral of B dot dl is equal to mu naught multiplied by the current ... | |
| Energy needed to tip over versus energy needed to tip back up again | 4/20/2011 |
| Q: Imagine a MagLIGHT brand flashlight... http://bit.ly/hcxlyI ...which has its batteries in its long ... A: Pushing the flashlight over will result in a net release of energy as the gravitational energy of ... | |
| physics | 4/20/2011 |
| Q: A green laser pointer has a wavelength of 540 nm (5.4 x 10^-7m). What is the frequency of this ... A: The speed of any wave is equal to the product of the wavelength and the frequency: s=f*L Therefore, ... | |
| index of refraction | 4/19/2011 |
| Q: A beam of light is incident at an angle of 28 degrees on a slab of flint glass. The refracted ray ... A: According to Snell's Law: n1*sin(<1)=n2*sin(<2) Assuming that this slab of glass is in air: n1=1.0 ... | |
| physics | 4/17/2011 |
| Q: Suppose the ray, in air with n = 1.00, enters a slab with n = 2.14 at a 27.8° angle with respect to ... A: 1) Applying Snell's Law: n1*sin(<1)=n2*sin(<2) To the first interface where: n1=1.0 [Assuming the ... | |
| Electric Dipole | 4/16/2011 |
| Q: If we consider a Gaussian surface around an ED the flux will be zero.So doesn't that mean E must be ... A: Gauss' Law does not say that the electric field is zero, only that the total electric flux through ... | |
| Gauss's Theorm.... | 4/16/2011 |
| Q: If Coulomb's law of electricity is violated and Force between two charged molecule is inversely ... A: Only in a universe where the area A of a "sphere" is proportional to R^(5/2). The reason Gauss' Law ... | |
| simple harmonic motion | 4/15/2011 |
| Q: Please help :/ A horizontal spring on a frictionless level air track has a 0.150 kg object attached ... A: This problem is an energy conservation problem. After the spring has been stretched the spring ... | |
| electricity | 4/14/2011 |
| Q: can a conducting solid sphere act as a capacitor? if yes then what is its capacity? A: Virtually ANYTHING can act as a capacitor! All it has to do is store positive charges separately ... | |
| Physics dealing with currents | 4/13/2011 |
| Q: The figure below is a cross section through three long wires with linear mass density 33 g/m. They ... A: The magnetic force Fm per unit length L between two parallel wires is given to be: ... | |
| physics | 4/13/2011 |
| Q: ∆1. KE=(1/2)mv^2 =(1/2)m(456)^2=103968 Spec heat of alum C=900j/kg/k C∆T=103968 chang ... A: Your calculation of the kinetic energy of the bullet is correct. Assuming that all of this energy is ... | |
| question | 4/12/2011 |
| Q: my name is Emmanuel Salmeron, well im go to JOHN F KENNEDY HIGH SCHOOL in silver spring md well i am ... A: Here is a very interesting suggestion - study the electric field near a plasma globe! All you will ... | |
| Oscillations Problem | 4/11/2011 |
| Q: A cylindrical can of diameter 10cm contains some ballast so that it floats vertically in water. The ... A: Assuming that the oscillation of this floating can is simple harmonic, the period of oscillation T ... | |
| physics | 4/10/2011 |
| Q: how to calculate positive and negative charge in 250 gram of water ? A: The molecular weight of water is: mw=2*H+O=2*1+16=18grams/mole Since you have 250 grams of water you ... | |
| Physics pendulum | 4/8/2011 |
| Q: Pendulum. A small rock with mass 0.12 kg is fastened to a massless string with length 0.80 m to form ... A: There are two distinct parts to this problem: energy conservation and then Newton's 2nd Law. First, ... | |
| statics of solid | 4/7/2011 |
| Q: a smooth hollow cylinder of radius r open at both ends, rest on a smooth horizontal plane. two ... A: There are two distinct parts to this problem; both involving Newton's 1st Law. 1) Use Newton's 1st ... | |
| acceleration/deceleration | 4/6/2011 |
| Q: Which combination of equations would I use to solve the following, please?: An arrow is fired and ... A: You do not indicate the direction in which this arrow is fired and that does matter. Assuming that ... | |
| Physics | 4/6/2011 |
| Q: A flat-bottomed rectangular boat is 4.0 m long and 1.5 m wide.If the load is 2000 kg (including the ... A: In order for a boat to float the buoyancy force Fb of the displaced liquid must be equal to the ... | |
| Waves & Sound. | 4/5/2011 |
| Q: Consider two speakers separated by a distance of 20 m and facing toward each other. The speakers are ... A: You don't say what the temperature is so I must assume that the speed of sound is somewhere between ... | |
| Newton's second law | 4/4/2011 |
| Q: I was unable to attend class the day this was covered. The notes I got from a friend have been no ... A: In any Newton's 2nd Law problem the first step is to make the freebody diagram. In this case there ... | |
| physics | 4/2/2011 |
| Q: A particle with a mass of 2.5×10^−5 kg and a charge of +2.2 µC is released in a (parallel ... A: [All of the following assumes that there is an electric field E directed towards the right.] The ... | |
| Rolling Ball | 4/1/2011 |
| Q: When a ball rolls down a curve and then rolls up the other side, it goes from Mass x Acceleration to ... A: I am not entirely sure what you are trying to ask. As a ball rolls down the curve the gravitational ... | |
| Trip or Slip? | 3/31/2011 |
| Q: A block of dimensions WxH and mass m is placed on a rough ssurface (coeff of friction=U).A ... A: If the box was going to tip over, it would do so about the far bottom edge. Assume that box is being ... | |
| chemistry | 3/30/2011 |
| Q: HOW MUCH POTASSIUM CHLORIDE HAS TO BE DISSOLVED IN WATER TO PRODUCE 2.0 LITERS OF A 2.45 M ... A: A 2.45 molar solution will contain 2.45 moles of solute [potassium chloride in this case] for every ... | |
| Pulley and masses | 3/29/2011 |
| Q: A heavy ball of mass 2m is kept on a smooth horizontal surface and the a lighter ball is dropped ... A: Not in this case. The axle of the pulley introduces an external force that changes the direction of ... | |
| chemistry | 3/29/2011 |
| Q: methane burns in air to produce carbon dioxide and water.what volume of carbon dioxide,at 1atm ... A: When methane is burned in air the balanced chemical equation will be: CH4+2*O2 - - - CO2+2*H20 ... | |
| physics | 3/27/2011 |
| Q: two spherical drops of equal size are falling vertically through air with a terminal velocity of ... A: Terminal velocity occurs when the drag force [in this case the frictional force of the air] balances ... | |
| Pulley and masses | 3/27/2011 |
| Q: A heavy ball of mass 2m is kept on a smooth horizontal surface and the a lighter ball is dropped ... A: This problem is essentially a momentum conservation problem. At the moment that the string gets taut ... | |
| Optics | 3/26/2011 |
| Q: A small gremlin from Academia finds itself d = 145 cm in front of a two-lens optical system as ... A: When you do any 2 lens problem you first solve for the position of the image produced by the first ... | |
| physics | 3/26/2011 |
| Q: The freeway off-ramp is circular with a 67 m radius and a slope of 14 deg. If the coefficient of ... A: This is a Newton's 2nd Law problem. first step of any Newton's 2nd Law problem is to make a free ... | |
| Relative Motion in Two dimensions | 3/25/2011 |
| Q: A plane is seen to travel in a direction [S 30 degrees W]. If its ground velocity was 300 km/h and ... A: This is a vector addition problem where the sum of the velocity of the wind Vwind and the velocity ... | |
| Physics, magnitude | 3/25/2011 |
| Q: Two tow trucks pull on a car that is stalled because of flooding. With reference to the East as 0 ... A: Ultimately this is a vector addition problem. The first step will be to break the two forces into ... | |
| Physics | 3/24/2011 |
| Q: I need help with formulating the formula for this problem: A small object of radius r and mass m ... A: For a rolling object the total energy is equal to the sum of the linear kinetic energy and angular ... | |
| Force and weight | 3/23/2011 |
| Q: "If it takes 5 newtons of force to lift an object off the floor and hold it up for 3 seconds, how ... A: I agree with your first impulse, it would take 5 Newtons of force to lift and suspend a 5 Newton ... | |
| Potential Energy and Energy Conservation | 3/22/2011 |
| Q: A 0.50kg mass is attached to a horizontal spring with constant k=100N/m. The mass slides across a ... A: Whether the object bouncing up and down or sliding side to side is irrelevant. Your initial equation ... | |
| Physics | 3/21/2011 |
| Q: Energy is released in nuclear fission because the average binding energy per nucleon of the fission ... A: Let me give you an example! A single carbon atom is made up of 6 protons, 6 neutrons and 6 ... | |
| Physics | 3/20/2011 |
| Q: Energy is released in nuclear fission because the average binding energy per nucleon of the fission ... A: Increased binding energy means that MORE energy will need to be added to an atom to pull it apart! ... | |
| Generate a current | 3/20/2011 |
| Q: Do you know of a list of household products like lemon juice that can generate a current. This year ... A: Easy to do with almost any fruit! I just did this with my students. Take an orange, a piece of ... | |
| Physics | 3/19/2011 |
| Q: Electrons are accelerated from rest through a potential difference of 10kV in an x-ray tube. ... A: A. The electrons will gain 10,000 eV of energy where 1 eV = 1.6 x 10^-19 J. Therefore, the energy ... | |
| mud pot and photograph | 3/17/2011 |
| Q: 1.Why the water in a mud pot is always cool? 2. When I see the photograph of any person, he/she is ... A: 1. As water evaporates from a mud pot it takes heat with it! In fact 540 calories of heat for each ... | |
| physics question | 3/16/2011 |
| Q: Hey I just have a few phyics questions I've been busting my brain on: "The problem asks In Fig. ... A: In the original position of e+ the potential energy Uo of the system is: ... | |
| Physics: Thermal expansion | 3/13/2011 |
| Q: "A 20.0 gram copper ring at 0 degrees Celsius has an inner diameter of D=.0254 meters. An aluminum ... A: This is fairly complicated and involved problem! Here are the steps you need to do. 1. Calculate the ... | |
| Speed Distance Power Weight | 3/12/2011 |
| Q: what if we have a car worth 1ton, 100Bhp, does a qarter mile(402.33m) in 18.00secs or a 0-100km/hr ... A: If you add 100 kg to a 1000kg car you will roughly increase the car's mass by 10%. This will affect ... | |
| Physics | 3/11/2011 |
| Q: A person weighing 134 pounds can run up 500 steps (each step is 0.20 m high) in 18 minutes and 37 ... A: Power is equal to work done per unit time: P=W/t=F*d/t=m*g*d/t Converting pounds into kilograms: ... | |
| distance | 3/10/2011 |
| Q: A 6000 kg truck going 30.0 m/s on a level road was slowed by applying a braking force of 22,500 N. ... A: There are 2 parts to this problem! First, use Newton's 2nd Law to calculate the rate of ... | |
| Resonance | 3/10/2011 |
| Q: I am trying to explain resonance, and I just want to make sure I've got it right. In particular, ... A: Your basic idea is correct. The resonant frequency of any object/system is the frequency at which ... | |
| Weight | 3/9/2011 |
| Q: I know an objects total mass, but how do I calculate the force required to move the object, on a ... A: You would need to know the frictional force that you will have to overcome. This value is probably ... | |
| physics help | 3/9/2011 |
| Q: a girl at a state fair swings a ball in a vertical circle at the end of a string. is the force ... A: Yes, the tension at the bottom of the swing has to be greater than the weight of the ball since at ... | |
| projectile motion | 3/8/2011 |
| Q: An object is thrown vertically upward such that it has a speed of 25 m/s when it reaches two thirds ... A: If the object is moving upward at 25 m/s, the final height of the object from this position can most ... | |
| Physics | 3/7/2011 |
| Q: An electron and proton are released at the same instance from the center of a pair of parallel ... A: If you use the kinematics displacement equation to describe the final displacement of each particle ... | |
| Magnitude of Falling Bodies Given Mass & Time | 3/3/2011 |
| Q: Consider two falling bodies. Their masses are 4.4 kg and 5.5 kg. At time t = 0, the two are released ... A: Final velocity does not depend on mass, only on time! The acceleration of all falling bodies, in the ... | |
| physics | 3/3/2011 |
| Q: There is a block of mass 2kg on a wood surface connected to a pulley with a hanging mass attached, ... A: According to Newton's 2nd Law the rate of acceleration a is directly proportional to the unbalanced ... | |
| Pendulums | 3/2/2011 |
| Q: Pendulum A is 20 cm long and has a 5g mass on it. Pendulum B is 30cm long and has a 10g mass on it. ... A: The period of a pendulum is given by: T=2*pi*sqrt[L/g] where L is the length of the pendulum. Since ... | |
| Physics - Electromagnetism | 3/2/2011 |
| Q: A 33 cm diameter coil consists of 24 turns of cylindrical copper wire 3.2 mm in diameter. A uniform ... A: According to Faraday's Law the emf is given by the change in magnetic flux divided by the time ... | |
| Introductory Physics | 3/1/2011 |
| Q: Find the coefficient of kinetic friction between a 3.85-kg block and the horizontal surface on which ... A: The force Fs applied by the spring will be: Fs=k*dx=850N/m*0.062m=52.7N Because the block is being ... | |
| kinematics problem solving | 3/1/2011 |
| Q: A bullet traveling at 1000 meters/second strikes a piece of wood and comes to rest 3 centimeters ... A: Assuming that the acceleration of the bullet is uniform, the average velocity of the bullet will be: ... | |
| Electromagnetics | 2/28/2011 |
| Q: A 10.2 cm diameter wire coil is initially oriented so that its plane is perpendicular to a magnetic ... A: The induced emf in a closed conducting path is given by Faraday's Law: Emf=-Dphi/Dt where Dphi is ... | |
| Work and Power | 2/27/2011 |
| Q: A 1930 kg car accelerates uniformly from rest to 14.3 m/s in 3.76 s. Find the work done on the car ... A: Work done is equal to the product of the force applied and the displacement of the object in the ... | |
| Physics | 2/27/2011 |
| Q: hi I need to know how I can state a relationship between force and acceleration (for a given mass) A: According to Newton's 2nd Law of motion the acceleration of a body is directly proportional to the ... | |
| Work Problem | 2/26/2011 |
| Q: Karen has a mass of 50.1 kg as she rides the up escalator at Woodley Park Station of the Washington ... A: In order to calculate work you need to multiply the force being applied [in this case the force of ... | |
| Work Problem | 2/26/2011 |
| Q: (a) In the 1950’s, an experimental train that had a mass of 40000 kg was powered across a level ... A: (a) Work is equal to the product of the force being applied and the displacement in the direction of ... | |
| Physics Homework Help | 2/25/2011 |
| Q: If you push a 34kg crate at a constant speed of 2.4 m/s across a horizontal floor (uk = 0.43), at ... A: The frictional force between two surfaces is equal to the product of the normal force pressing the ... | |
| What is the force of impact? | 2/24/2011 |
| Q: Will the force of impact of a 8 inch piece of hail dropping from the sky be the same force of impact ... A: Since the diameter of the 8" hailstone is twice the diameter of the 4" hailstone, the 8" hailstone ... | |
| Potential energy of a system | 2/23/2011 |
| Q: There are two dust particles of equal mass and equal positive charge. They are separated by a ... A: Yes! In fact it is just this argument that leads many cosmologists and physicists to argue that the ... | |
| angular velocity and linear velocity | 2/21/2011 |
| Q: Do you know the relation between the balance and the angular velocity and the linear velocity in the ... A: You can't add angular velocity to linear velocity any more than you can add apples to codfish! ... | |
| Physics | 2/20/2011 |
| Q: Can you assist me with this? An 8 k8 shot makes 7 complete revolutions during it 2.5 sec flight. If ... A: 7 complete revolutions is: 7*2*pi=44rad If the flight lasts for 2.5 seconds the resulting angular ... | |
| Ping pong balls | 2/20/2011 |
| Q: Which surface do ping pong balls bounce higher on?? The surfaces are floorboards, concrete, carpet, ... A: Concrete will generate the greatest rebound. Why? Because very little energy will be lost to the ... | |
| physics | 2/19/2011 |
| Q: An individual lifts a 100 kg weight to a height of 1.9m a) how much work was done? when the weight ... A: Since work is equal to the product of force and distance through which that force has been applied, ... | |
| Magnitude and friction | 2/18/2011 |
| Q: A 10 kg block sitting in a horizontal surface is subjected to a horizontal force of 150N. If the ... A: To accelerate this crate to the right the applied force must do 2 things: overcome the force of ... | |
| time | 2/18/2011 |
| Q: I need to figure out the time of a falling object to figure out the speed. I need to find how long ... A: This is a standard kinematics problem where: Do=600ft [the initial position of the object], Df=0m ... | |
| Physics | 2/16/2011 |
| Q: with what force does a rock that weighs 10 N strike the ground if dropped from a rest position 10 m ... A: The problem has no straight forward answer because there is none! The force exerted on the ball by ... | |
| Pendulum Problem | 2/16/2011 |
| Q: Given: There is a 5kg sphere hanging in a pendulum mechanism at a fixed point. The sphere is hanging ... A: Since gravitational energy is: GPE=m*g*dh, if the pendulum loses 10% of its energy during its swing ... | |
| Physics | 2/15/2011 |
| Q: Do you mind helping with this qiestion please. A camper heats up 25 L of water to boiling to get ... A: The heat gained by the cold will be equal to the heat lost by the hot water. Since heat gained or ... | |
| Pressure, Temp and Volume | 2/13/2011 |
| Q: Can you explain this to me please? The pressure, temperature and volume of a sample gas are P, T ... A: The ideal gas law says: P*V=n*R*T I'd you divide this equation by itself: P2*V2=n*K*T2 P1*V1=n*R*T1 ... | |
| Physics | 2/11/2011 |
| Q: A 40.0mA current is carried by a uniformly wound air-core solenoid with 450 turns, a 15.0mm diameter ... A: The magnetic field within a long solenoid is given by: B=mu*n*I where mu=4*pi*10^-7 is the ... | |
| Physics (Mechanical energy) | 2/11/2011 |
| Q: A body of mass 4kg was dropped vertically from a storey building 80m high. Calculate the velocity of ... A: All kinematics problems involve 6 distinct variables: Do, Df, Vo, Vf, a & t as well as 2 available ... | |
| Physics | 2/10/2011 |
| Q: Gasoline flows into a storage container at the rate of 32.5 gal/min. The storage container is 13 ft. ... A: The first thing you need to do is to calculate the volume of the tank in gallons. In this case the ... | |
| Tipping independent objects stacked | 2/10/2011 |
| Q: I have pallets with product on them of a known weight and size stacked vertically in a warehouse. I ... A: This is essentially a question of opposing torques. If the fork of the forklift applies a horizontal ... | |
| Energy, Power, Machines | 2/9/2011 |
| Q: I don't understand the following... 1. A 500-N crate needs to be lifted 1 meter vertically in order ... A: c) It doesn't matter how you increase the height of the crate. Either path will do so since ... | |
| physics | 2/8/2011 |
| Q: Can you tell me if I am correct in my choice of answers? 1) Consider the directions of the velocity ... A: 1) Sorry, no. The correct answer is "a". For an object moving in a circular path the velocity vector ... | |
| velocity of a pitched baseball | 2/8/2011 |
| Q: does the velocity of a pitched baseball have any bearing on the distance a batter can hit the ball A: I could only speculate on the details of your question due to the complexity. However, it turns out ... | |
| Fall | 2/7/2011 |
| Q: Students in a lab measure the speed of a steel ball to be 8 m/s when launched horizontally from a ... A: Using kinematics in the vertical direction the variables will be: Do=1.0m [the initial vertical ... | |
| physics | 2/7/2011 |
| Q: Can you help me with this question please? A stunt man (69.4kg) swings across a valley at the end ... A: There are 2 steps to this problem: first find the speed of the stunt man at the bottom of the swing ... | |
| Physics | 2/6/2011 |
| Q: Can you help with this question. I am getting a negative number which I do not think is correct.. A ... A: There is a bit of inconsistency in this problem! If you use the vertical information the kinematics ... | |
| Physics | 2/6/2011 |
| Q: Can you help? a pail of water is rotated in a vertical circle of radius 1.00 m (a) what are two ... A: a) There are two important forces acting on the pail: the force of gravity Fg - down and the normal ... | |
| physics | 2/5/2011 |
| Q: Can you assist with this question please? A badminton shuttlecock is struck by a racquet at a 35 ... A: This is a really hard problem unless you make the unrealistic assumption that air friction is ... | |
| Weights in containers | 2/4/2011 |
| Q: I have a two partYou have an open topped lorry on a set of scales and a chicken inside the lorry. ... A: In an open top lorry the answer is not so clear at what it would be in an enclosed vehicle. If the ... | |
| Physics-Force | 2/3/2011 |
| Q: A force of 20N distributed uniformly over an area of 20cm sq,find pressure in pascals?PLZzzzz help ... A: Pressure in Pascals is calculated by dividing e force in Newtons by the area in square meters. Since ... | |
| Research Paper | 2/3/2011 |
| Q: what is static Friction? A: Static frictional force between two surfaces when the 2 surfaces involved are NOT sliding relative ... | |
| Particles being heated and gaining energy. | 2/2/2011 |
| Q: I know that when you heat gas particles, they gain more energy and fly around faster. Is there any ... A: The average kinetic energy of the molecules of a gas is related to the temperature according to: KE ... | |
| Physics | 2/1/2011 |
| Q: The gravitational pull between two spheres in outer space is 25 newtons. What would the wieght of ... A: Assuming that you mean that the mass of each sphere is cut in half, the new force will be 1/4 the ... | |
| physics-electrostatics | 2/1/2011 |
| Q: http://staff.fcps.net/KGILL/AP%20Physics/AP%20Extra%20Homework/electfields.pdf please look at that ... A: 19) This problem is about adding electrostatic fields together. Since they are vectors you will need ... | |
| accelerometer measurement | 1/31/2011 |
| Q: I was so excited when I heard that a smartphone contains accelerometers. I figured I could move a ... A: According to the General Theory of Relativity - and confirmed by the accelerometer built into the ... | |
| Physics | 1/31/2011 |
| Q: I am trying to help my 14 year old with two questions that he has left to answer. Any help would be ... A: 1. Work is equal to the product of the force being applied multiplied by the distance through which ... | |
| physics | 1/30/2011 |
| Q: If you lift a 40N package straight up to a height of 1.5 meters (about shoulder height), a. how much ... A: Work is equal to the product of the force applied and the resulting displacement: W=F*d In this ... | |
| Physics HW Question | 1/30/2011 |
| Q: Points A, B, and C are at the vertices of an equilateral triangle. A certain positive charge q ... A: The new electric field will be the vector sum of the two fields caused by the charges at locations A ... | |
| physics | 1/29/2011 |
| Q: can you help with these two problems please 1). A 6.36 gram bullet moving at 272 m/s penetrates a ... A: 1) The easiest way to solve this problem is to use the "impulse" equation: F*dt=m*dv [This is a ... | |
| Question | 1/29/2011 |
| Q: If a lighter person and a heavier person jump the same distance off the ground, who will burn more ... A: Since work is equal to force times distance and since more force will be needed to lift a heavy ... | |
| uncertainties | 1/27/2011 |
| Q: If p = q + r, and σq and σr are the uncertainties in the measurements of q and r, what is ... A: When you add two quantities with error [uncertainty] the error in the sum is equal to the sum in the ... | |
| physics | 1/27/2011 |
| Q: I'm not quite sure how to do this problems. Calculate the acceleration of a person standing near ... A: The person standing on the Merry-Go-Round is accelerating centripetally [any acceleration which ... | |
| Physics Project | 1/26/2011 |
| Q: I need to figure out 2 specific examples of how the equation impulse = change in the momentum ... A: Impulse is defined to be the change in momentum. In this case the initial momentum of the paintball ... | |
| Physics Vertical Throw | 1/26/2011 |
| Q: An arrow is shot vertically upward and then 2.10 s later passes the top of a tree 37.3 m high. How ... A: First step set up the data table identifying as many of the 6 kinematics variables as possible! ... | |
| physics | 1/24/2011 |
| Q: A cannon is placed at the base of a mountain. We tilt the cannon at a 45-degree angle, in the ... A: All kinematics problems have 6 possible variables: Do, Df, Vo, Vf, a and t, as well as 2 available ... | |
| physics | 1/23/2011 |
| Q: Can you help with this? Two objects with masses of 3.00 kg and 5.00 kg are connected by a light ... A: This is a Newton's 2nd Law problem. The first step will be to make freebody diagrams for each mass: ... | |
| Physics | 1/20/2011 |
| Q: Hey, why is it that the voltage in a parallel circuit is the same? ANSWER: Voltage is really ... A: Potential difference is the difference in the potential at two different points in an electric ... | |
| Physics | 1/18/2011 |
| Q: Can you help me to solve the question attacted? A: If you are referring to the problem in the bottom right corner, assume that the current I1 in the ... | |
| Physics | 1/18/2011 |
| Q: Hey, why is it that the voltage in a parallel circuit is the same? A: Voltage is really "potential difference" which means exactly what is says, it is a difference in ... | |
| Physics | 1/17/2011 |
| Q: A German U12 rocket from the second world war had a range of 300 km, reaching a maximum height of ... A: Assume that the initial velocity of the rocket is V at and angle Q above the horizontal. The initial ... | |
| physics-latent heat of fusion(ice) calorimeter | 1/16/2011 |
| Q: 1. would it be possible for a set up to arrive at a final temperature lower than the initial ... A: 1) Sure, Think about the cold packs used in athletic events where a compound is formed that in the ... | |
| Electron photon collision- electron orbit jump | 1/15/2011 |
| Q: 1.Does a photon have angular momentum? 2.Can angular momentum be conserved about the nucheus when an ... A: 1. Yes, a photon has a spin of 1 2. Not only can angular momentum be conserved, angular momentum ... | |
| Conservation of Energy with angle | 1/13/2011 |
| Q: I have a problem. a ball was launched at an angle 45 degrees above the horizon on a cliff 256m high ... A: Because energy must be conserved the total energy of the ball as it leaves the top of the cliff must ... | |
| physics | 1/13/2011 |
| Q: A 50 kg box is sliding along the floor when it encounters a ramp. The force of friction on the box ... A: Since energy must be conserved we need to account for all of the energy both at the beginning of the ... | |
| Sir,I have physics problem.I dont know the steps and working | 1/12/2011 |
| Q: Two speakers are driven by the same oscillator of frequency 200 Hz. They are located on a vertical ... A: Interference between two point sources occurs when the path length difference between the observer ... | |
| PHYSICS | 1/12/2011 |
| Q: Q.1) IF THE SPEED OF A WAVE IS DOUBLED, WHILE THE FREQUENCY REMAINS THE SAME, WHAT HAPPENS TO THE ... A: 1) Since the speed of a wave is equal to the product of the wave's wavelength and its frequency: ... | |
| forces and laws of motion | 1/10/2011 |
| Q: while deciding where to drive a supporting nail, you are pressing a 18 N picture frame against the ... A: This is a Newton's 1st Law problem. The first step will be to make the freebody diagram. In this ... | |
| Hockey Physics Problem | 1/9/2011 |
| Q: A player strikes a hockey puck giving it a velocity of 53.889 m/s. The puck slides across the ice ... A: The first step here will be to determine the acceleration of the hockey puck as it slides across the ... | |
| High Mass and Velocity Collisions | 1/9/2011 |
| Q: If an object weighing 2 million pounds and moving at a speed of 15,000 MPH collides head-on with an ... A: In order to answer your question you would need to know how far each object moves during the ... | |
| a query related regardiing force | 1/8/2011 |
| Q: good morning sir I would be glad to know the answer for my question. A ball of any density is ... A: When you drop an object in air Newton's 1st Law applies until the object reaches its terminal ... | |
| phys | 1/6/2011 |
| Q: If a rock is thrown at a speed of 10m/s at an angle of 30 above the horizontal.. ..what will be the ... A: Almost all 2 dimensional kinematics problems can be solved in the same way! There are 6 distinct ... | |
| Simplest steam engine | 1/5/2011 |
| Q: I am trying to make the simplest cheapest low-tech steam engine possible. Is there a water mixture ... A: What you are describing is NOT a steam engine. Your description sounds more like a typical internal ... | |
| Pressure | 1/4/2011 |
| Q: Pressure is force/area.A brick on the table will have force=mg and the pressure will be ... A: As long as there is no water flowing out of the hose the pressure on the walls of the hose will be ... | |
| interference | 1/3/2011 |
| Q: i wanted to know that where do this formula ( phase difference=(2pi/wavelenth)*path difference) came ... A: The 2pi you have included is an angle in radians, the wavelength L will be in meters and the ... | |
| static energy | 1/2/2011 |
| Q: A particle of mass 21 g and charge 20 µC is released from rest when it is 35 cm from a second ... A: The electrostatic force Fe between these two charges will be determined by: Fe=k*q1*q2/r^2 Where ... | |
| Electromagnetism | 1/2/2011 |
| Q: I would like to know if two conducting charged spheres of radius R1 and R2 were put in contact, how ... A: If you touch two conducting spheres together their electric potential would have to be the same. If ... | |
| Stopping a 3t vehicle compare to 1t vehicle | 1/1/2011 |
| Q: I would be grateful for your assistance to answer the following. I would like to know the stopping ... A: Theoretically they would both stop in the same distance! If you apply Newton's 2nd Law to this ... | |
| mathematics | 1/1/2011 |
| Q: There is one ship that is 200 metres in length. A second ship is 100 metres in length. The two ships ... A: This problem can best be solved by using D=v*t where v is the relative velocity between the two ... | |
| Calculating the work of a float | 12/30/2010 |
| Q: A water vessel that is occasionaly filled and emptied with one cubic meter of water has a float that ... A: Work done is equal to the force applied multiplied by the distance through which the object has ... | |
| physics | 12/29/2010 |
| Q: (Im having a hard time answering this, please help) A photon-powered spacecraft of mass 10.0 kg ... A: If the wavelength of the light is L=225nm the energy U of each photon can be predicted from: U=h*c/L ... | |
| Humidity inside a room | 12/28/2010 |
| Q: I'm not sure if you are the right person to ask this, but here it goes. My question is this: Where ... A: Unless you have sealed the walls of your house with a vapor barrier the water vapor is leaking out ... | |
| auto impacts | 12/26/2010 |
| Q: If a small car (2500 lbs.)going 3 mph, hits a larger one from behind (3700 lbs.) which is stopped ... A: Assume that when the small car collides with the heavier car at 3mph (4.4ft/s) and that during the ... | |
| Kinematics problem | 12/24/2010 |
| Q: I would be very pleased if you help me to solve this problem, A ball of 1 kg falls from a height of ... A: This problem can be solved by using Newton's 2nd Law because the object is accelerating: SF=m*a ... | |
| truck and bridge | 12/22/2010 |
| Q: There's a bridge that can only hold 6000 kg, however a truck weighing 9000 kg drove on it and ... A: It really depends on what it means to say that the bridge can only hold 6000kg. I would assume that ... | |
| Uniform Circular Motion | 12/20/2010 |
| Q: A centrifuge is a device in which a small container of material is rotated at a high speed on a ... A: Centripetal acceleration is given by: ac=V^2/R If the centripetal acceleration in the centrifuge is ... | |
| circular motion and conservation of energy | 12/19/2010 |
| Q: A block of metal is placed on top of a half - sphere made of ice. The block slides on the half - ... A: The metal object will leave the surface when the normal force between the sphere and the metal ... | |
| Uniform Circular Motion | 12/18/2010 |
| Q: Two satellites are in circular orbits around the earth. The orbit for satellite A is at a height of ... A: A satellite orbiting the Earth is acceleration centripetally and is, therefore, following Newton's ... | |
| Work and Energy | 12/18/2010 |
| Q: "Rocket Man" has a propulsion unit strapped to his back. He starts from rest on the ground, fires ... A: The work done by the backpack will be equal to the energy gained by the rocketman! In this case the ... | |
| physics | 12/17/2010 |
| Q: a 6.0 kg block of ice rests on a surface that is tilted by 12 degrees. find the acceleration of the ... A: The only force acting to accelerate the block of ice along the tilted surface is the component of ... | |
| Momentum | 12/16/2010 |
| Q: A pendulum consists of a 0.4-kg bob attached to a string of length 1.6m. A block of mass m rests on ... A: This problem is a 2 part problem involving two different fundamental principles: energy conservation ... | |
| PHYSICS | 12/15/2010 |
| Q: Aluminum Rod #1 has a length L and a diameter d. Aluminum rod #2 has a length 2L and a diameter 2d. ... A: Assume that the elastic coefficient for the first rod is k1. Because the second rod has 2x the ... | |
| Physics | 12/14/2010 |
| Q: Given that q = +12 u(micro-) Coulomb and d = 16cm, find the direction and magnitude of the net ... A: The electrostatic force between two charges is given by: F=k*q1*q2/R^2 To find the net electrostatic ... | |
| Cannonball Problem | 12/14/2010 |
| Q: My teacher had solved it for us, but I had copied it into a notebook which I, unfortunately, lost. ... A: All 2 dimensional kinematics problems can be solved in the same way! There are 6 kinematics ... | |
| Lifting Fans | 12/13/2010 |
| Q: How much force must a fan put out to lift a person strait up into the air more than a foot? Also how ... A: The fan must produce a force equal to the weight of the person! I do not know specifically how big ... | |
| Physics question | 12/12/2010 |
| Q: Calculate the period of a ball tied to a string of length 0.3 m making 1.9 revolutions every second. ... A: The period T is the time required for 1.0 revolution. Since this ball is doing 1.9revolutions per ... | |
| Physics | 12/11/2010 |
| Q: Just telling me what the formulas are for all of the problems in layman's terms would be great. A ... A: This problem is just like the previous problem. I have posted that solution below. "Since the plank ... | |
| Physics | 12/11/2010 |
| Q: Just telling me what the formulas are for all of the problems in layman's terms would be great. I do ... A: Since the plank is not accelerating it is at equilibrium. If it is at equilibrium 2 conditions must ... | |
| Einstein's relativity | 12/10/2010 |
| Q: I have a good reason for not wanting to believe in Einstein's relativity/special relativity ... A: Einstein's Special Theory of Relativity has been experimentally confirmed thousands if not millions ... | |
| physics help | 12/9/2010 |
| Q: A 5 kg block of iron is suspended in water by a cord attached to a scale. What does the scale read? ... A: Since the iron mass is suspended in the water it must be at equilibrium. If it is at equilibrium the ... | |
| physics | 12/9/2010 |
| Q: A 100-kg man and a 60-kg man have a tug-of-war. The 100-kg man pulls on the rope such that the 60-kg ... A: According to Newton's 2nd Law the sum of the forces SF acting on a mass m in the direction of the ... | |
| Physics | 12/8/2010 |
| Q: A sports car and a bus are both traveling at 30 km/hr. Which of the two will require more force to ... A: The amount of force needed to stop either vehicle will depend on how much work is needed to remove ... | |
| moment of inertia | 12/8/2010 |
| Q: Mass m1=5kg is located on the y-axis at y=-50cm and mass m2=10kg is located on the x-axis at ... A: The moment of inertia I of a mass m is equal to the product of the mass and the square of the ... | |
| physics | 12/7/2010 |
| Q: A strong man stands in the street and pushes against a car as hard as he can when it drives toward ... A: He would have to be VERY strong, but in any case the force he exerts on the car would have to be ... | |
| Central force motion | 12/6/2010 |
| Q: a. Explain why eccentricity = 0 represent a circular orbit A: The eccentricy of an ellipse is a measure of how nearly circular the ellipse is. Eccentricity is ... | |
| heat | 12/6/2010 |
| Q: Water falls a distance of 50.0 meters. The specific heat of water is 1.00 cal/gm°C. What is the ... A: As the water falls its gravitational potential energy, GPE=m*g*dh, becomes thermal energy Q=m*c*dT. ... | |
| physics | 12/5/2010 |
| Q: at what height can a 1500kg satellite circle the earth with a velocity of 200m/s? A: An orbiting satellite is moving in a circular path and is, therefore, accelerating. Since it is ... | |
| AP Physics | 12/5/2010 |
| Q: A ladder of unknown length and mass of 29 kg rests on a rough floor, and leans against a rough wall. ... A: This is clearly a Newton's first law problem. The first step is to identify all of the external ... | |
| AP Physics; Momentum | 12/4/2010 |
| Q: A 2700 kg car traveling to the north is slowed down uniformly from an initial velocity of 25.8 m/s ... A: First solve for the acceleration using Newton's 2nd Law, SF=m*a, where SF=-7350N and m=2700kg; solve ... | |
| Physics question | 12/3/2010 |
| Q: A box slides down a ramp inclined at 34◦ to the horizontal with an acceleration of 2.26 m/s2. ... A: Since the box is accelerating Newton's 2nd Law applies. The first step will be to identify all of ... | |
| physics | 12/3/2010 |
| Q: a) If the mass of a golf ball(46g) coul be converted entirely into energy(E=mc^2), how much energy ... A: Using E=m*c^2: E=0.046kg*(3.0*10^8m/s)^2=4.14x10^15J One kilowatt hour of electricity correspond to: ... | |
| The cartesian diver.... | 12/2/2010 |
| Q: Suppose you were creating a Cartesian diver but you used the following instead. What if anything ... A: A. Since oil is less dense than water you will have to reduce the average density of the diver - add ... | |
| The LHC | 11/30/2010 |
| Q: The LHC states it has created very, very small black holes by colliding particles close to the speed ... A: Interestingly such mini black holes are probably being formed all the time by natural cosmic rays, ... | |
| physics | 11/29/2010 |
| Q: A basketball player is balancing a spinning basketball on the tip of his finger. The angular ... A: Rotational kinematics problems can be done using the same technique as linear kinematics problems! ... | |
| physics | 11/29/2010 |
| Q: A 62.0 kg person, standing on a diving board, dives straight down into the water. Just before ... A: Use the impulse equation, F*dT=dP, where F is the average force, dT is the time interval over which ... | |
| Friction | 11/27/2010 |
| Q: Climbers attempting to cross a stream place a 340 kg log against a vertical, frictionless ice cliff ... A: This problem is a Newton's 1st Law problem that involves both conditions that are necessary for a ... | |
| Capacitive Barometer | 11/25/2010 |
| Q: I want to add a non-liquid barometer to my observatory. I came up with the idea of using a ... A: Why not use the heat shrink plastic used to seal windows during the winter. This is available at ... | |
| creating an electromagnet | 11/24/2010 |
| Q: I am wanting to create and electromagnet with an air core (or possibly an iron core, whichever is ... A: I don't really think that an "equation" be of much use here. This is what I suggest you do instead. ... | |
| EM radiation | 11/23/2010 |
| Q: When an electric field is applied across a metal this causes the "free" electrons to flow and this ... A: In a conductor the valence electrons, the ones involved in current flow, can be found in "s shell" ... | |
| physics;kinematics in one dimension | 11/23/2010 |
| Q: you are driving home from school steadily at 65 mi/hr. for 130 miles.it then begins to rain and you ... A: During the first 2.0 hours the car goes 65 mph and so the time for this part of the trip is: ... | |
| stealth technology in planes | 11/22/2010 |
| Q: stealthy planes are made up of special meterial which is "light resistance",I want to know that ... A: The two primary modes of stealth are: absorb the incoming radar beam and reflect the radar in any ... | |
| Physics | 11/21/2010 |
| Q: A ball is projected horizontally from the edge of a table that is 1.21 m high, and it strikes the ... A: The first step here is to find the horizontal velocity of the ball. To do this you need to find the ... | |
| angular displacement | 11/20/2010 |
| Q: A fan rotating at 2.1 radian/s slows down with a constant acceleration and comes to a stop in a ... A: Although this problem is rotational rather than linear, the relationships for rotational motion are ... | |
| physics | 11/20/2010 |
| Q: Electrons are ejected from a surface with speed ranging up to 669km/s when light with a wavelength ... A: According to the photoelectric equation: KE=h*f+phi=h*[c/lambda]+phi where KE is the kinetic energy ... | |
| physics temperature problem | 11/19/2010 |
| Q: I already asked you part of this problem, I figured out some other questions that went along with ... A: The added ice must do two things: increase in temperature to 0oC and cool the water to 0oC. Relative ... | |
| temperature physics problems | 11/18/2010 |
| Q: 0.1kg of ice initially at a temperature of -10 degrees Celsius is added to a cup with .5kg of water ... A: There are four distinct steps to this problem: 1. How much heat is needed to bring the ice up to the ... | |
| physics | 11/18/2010 |
| Q: A college rower can easily push a small car along a flat road, but she cannot lift the car in the ... A: Simple! Much more force is needed to lift the car than to push the car. To lift a car requires a ... | |
| Calculus | 11/17/2010 |
| Q: A tennis ball is thrown vertically in the air and lands after 2.1 seconds. Given the velocity ... A: As far as I can tell this problem does not involve any calculus. This is a typical one dimensional ... | |
| physics | 11/16/2010 |
| Q: 1)how the frequency and wavelength of light is related to its refraction through different medium? ... A: 1) As a light wave changes mediums its frequency remains the same. Since the speed of a wave through ... | |
| Magnets | 11/14/2010 |
| Q: Suppose you drop a magnet and a non-magnetized object through a long vertical copper pipe. You ... A: When a magnet falls through the copper pipe the changing magnetic field [caused by the motion of the ... | |
| collisions | 11/10/2010 |
| Q: I can't seem to figure out the speed when there are two different masses. 1)A 2.0 kg ball at rest ... A: For all momentum conservation problems involving two objects: m1*v1+m2*v2=m1*v3+m2*v4 where v1 and ... | |
| physics | 11/9/2010 |
| Q: a length of thin-walled cylindrical copper tubing of radius 3cm stands on a smooth horizontal ... A: It doesn't matter! Since both ball bearings fall within the boundaries of the cylinder's footprint ... | |
| Science question | 11/9/2010 |
| Q: I am standing in a bus moving at a constant speed of 35 mph. If I throw a ball straight up into the ... A: The bus, you and the ball are all moving at a constant velocity in the horizontal direction. When ... | |
| thermal expansion | 11/8/2010 |
| Q: A pendulum clock consists of an iron rod connected to small, heavy bob.If it is designed to keep ... A: The linear thermal expansion of a solid is given by: dL=L1*alpha*dT where dL is the change in ... | |
| tension | 11/8/2010 |
| Q: Suppose that a line were stretched almost perfectly horizontally between two poles that are 21 ... A: If the wire sage 10 cm the angle Q between the wire and the horizontal can be found by using the ... | |
| Please Help | 11/7/2010 |
| Q: Explain why the smallest fragments from an explosuon can cause damage over a wide area? Thank you A: When an explosion occurs chemical potential energy is converted into the kinetic energy of the ... | |
| question | 11/6/2010 |
| Q: A particle starts from the origin at t=0 with an initial velocity of 5 m/s along the positive ... A: a. Since final velocity is equal to: Vf=a*t+Vo And since in this case: a=(-3i+4.5j), t=2s and Vo=5i ... | |
| physic | 11/6/2010 |
| Q: A projectile-buoy target lies 100m away.Determine at least one possible set of values for the ... A: Maximum range of a 2 dimensional projectile occurs when the launch angle is 45 degrees so let's ... | |
| physics | 11/5/2010 |
| Q: At the instant the traffic lights turn green, an automobile that has been waiting at an intersection ... A: First identify the 6 kinematics variables for the car: Do=0m [given], Df=? unknown], Vo=0m/s ... | |
| Physics | 11/5/2010 |
| Q: A bus driver forgets to stop at a bus stop. Just as he passes the stop, he begins to decelerate. ... A: All one dimensional kinematics problems can be solved in the same exact way! There are 6 possible ... | |
| Physics | 11/4/2010 |
| Q: A bus starts from rest at a station and accelerates at a rate of 2 m/s for 25 s. It then runs at ... A: The easiest way to do this, in my opinion, is to make a graph plotting the velocity of the bus as a ... | |
| Work Energy Theorem | 11/4/2010 |
| Q: How does the Work-energy theorem explain why anti-lock (normal brake situation)brakes are good for ... A: That's because it does not relate. Anntilock brakes are not about the work-energy theorem, but are ... | |
| hmm im bad with equations i need for future reference and i forget these | 11/3/2010 |
| Q: How would you determine the center of mass for a long piece of wood? Just the equations A: To find the center of mass of a set of discrete objects you multiply each object's mass by its x ... | |
| Physics acceleration | 11/2/2010 |
| Q: I've got a question about the internal combustion engine. The piston has a displacement of 10 cm. ... A: Since the piston represents a one dimensional component of the rotational motion of the crankshaft ... | |
| light-speed & a merry-go-round | 11/1/2010 |
| Q: What would be the diameter of a merry-go-round whose outside edge is moving at light-speed? A: This is an if-then statement where the if part is false. Therefore, it is really impossible to ... | |
| total acceleration vector just before string breaks | 10/31/2010 |
| Q: With a mass at the end of a string in a vertical circular orbit, how might one figure out the ... A: If you spin an object in a vertical circle the tension in the string will be greatest at the bottom ... | |
| coulombs force law/electromagnetics | 10/30/2010 |
| Q: i was hoping you could check if my answer was correct. The question is -Estimate the charge present ... A: Why would you say that gravity has no effect on atoms? This is just not true. Your analysis seems ... | |
| not sure | 10/29/2010 |
| Q: My boyfriend was hit in the head at work the other day by a 100 pound pole that fell approximately ... A: That is very difficult to answer exactly but we can make some estimates. If the pole fell from a ... | |
| constant acceleration | 10/28/2010 |
| Q: A person standing at the edge of a roof throws sphere A vertically upward with an initial velocity ... A: As ball A moves upward it is accelerated downward by gravity a=-g. This results in a change in the ... | |
| Physics | 10/28/2010 |
| Q: An 8.4 g bullet leaves the muzzle of a rifle with a speed of 621.5 m/s2. what constant force is ... A: The easiest way to do this is to use the impulse form of Newton's 2nd Law! Ordinarily Newtons' 2nd ... | |
| wave propagation | 10/27/2010 |
| Q: We have read that wavelength is the distance between two consecutive crests, and wave height is the ... A: The problem here is your definition of "wave height". The correct term is "amplitude" and is defined ... | |
| Physics homework question help! | 10/27/2010 |
| Q: A 46 gram golf ball is dropped on a sidewalk from a height of 2.0 meters and rebounds to a height ... A: Impulse will be equal to the change in momentum of the ball: Pf-Pi So what you need to do is to ... | |
| motion | 10/26/2010 |
| Q: My girlfriend Father asked me this question. A bird is flying inside a train travelling at a speed ... A: You are correct, the bird will collide with the forward wall of the train car. The bird is initially ... | |
| Physics | 10/24/2010 |
| Q: a man pushes a 40 kg box up a 20° slope by applying a force P at 30° to the slope surface. What is ... A: Your first equation: F_p*cos30=-F_f-F_g*cos20 Should be: F_p*cos30=-F_f+F_g*sin20 Your second ... | |
| physics | 10/23/2010 |
| Q: At what point will the string be most likely to break for a lead ball being swung in a vertical ... A: When the lead ball is swinging in a vertical circle the string is most likely to break at the ... | |
| Physics, acceleration | 10/21/2010 |
| Q: An airport has runways only 200 m long. A small plane must reach a ground speed of 40 m/s before it ... A: All one dimensional kinematics problems can be solved in the same way. In kinematics there are 6 ... | |
| linear momentum and collision | 10/20/2010 |
| Q: I tried to work through this and came up with something really long and weird looking....i'm ... A: There are a number of steps that must be used to answer this question! 1. Use momentum conservation ... | |
| physics | 10/20/2010 |
| Q: - Business - Computers - English - Foreign Languages - Health - Home Economics - Math - Music - ... A: When you drop the stone from the roof of the building to the ground the required time can be ... | |
| Physics, Tension forces | 10/19/2010 |
| Q: A tow truck is connected to a 1400 kg car by a cable that makes a 25 degree angle to the horizontal. ... A: Since the cable makes an angle of 25 degrees with the horizontal the component of the tension in the ... | |
| Parabolic Motion | 10/19/2010 |
| Q: A projectile is shot with an in initial velocity of 101 m/s at and angle of 45 degrees follows a ... A: At the highest point of its trajectory the projectile will be traveling horizontally and only the ... | |
| finding magnitude | 10/18/2010 |
| Q: Image attached: I've been trying to figure out how to find force for b, d, e, g and h. For b would ... A: How much force would be required to lift the mass and the string/chain/spring? Just add the weight ... | |
| Physics | 10/16/2010 |
| Q: There is a 100 m high tower. It shoots a cannon ball horizontally with an initial velocity of 8,000 ... A: Effectively what you need to do here is to calculate the orbital velocity of a satellite at an ... | |
| Modern Physics | 10/15/2010 |
| Q: a charged water drop of weight (6x10^-14)N falls at a terminal speed of (0.15mm s-1) in air between ... A: Since the droplet is falling at terminal velocity the gravitational force on the drop must be ... | |
| Electric Potential and Charge | 10/14/2010 |
| Q: Two point charges 3.0 cm apart have an electric potential energy -120 microJoules. The total ... A: Electrostatic potential U is given by: U=k*q1*q2/r where k=9.0x10^9Nm^2/C^2 is the electrostatic ... | |
| Newton's 3rd Law | 10/13/2010 |
| Q: Sir, please help me with this homework question. I just don't understand and I have used up all but ... A: If you apply Newton's 2nd Law [SF=m*a] to the entire system the sum of the forces SF is equal to the ... | |
| kinematics | 10/12/2010 |
| Q: standing at the edge of a cliff 32.5m high, you drop a ball. Later, you throw a second ball downward ... A: The accelerations of both balls will be the same. The ball thrown downward will reach the ground in ... | |
| modern physics | 10/12/2010 |
| Q: if uncertainty in location of a particle is equal to its de-brogile wavelength. What is the ... A: According to the Uncertainty Principle the uncertainty in momentum multiplied by the uncertainty in ... | |
| Question on friction | 10/9/2010 |
| Q: A ladder 5m long inclined on a smooth wall at 4m above the ground and 3m from the wall at a rough ... A: This is a Newton's 1st Law problem that involves both force and torque. The first step is to make a ... | |
| motion | 10/9/2010 |
| Q: why does an apple in the coach of train does not collide to the wall of coach when it is thrown in ... A: Because when you toss the apple upward the apple is already moving horizontally in you hand at the ... | |
| projectile motion | 10/8/2010 |
| Q: Romeo is tossing pebbles at Juliet's window and wants the pebbles to hit the window gently, with ... A: I would like to suggest a completely different approach! Fundamentally, all 2 dimensional kinematics ... | |
| Physics | 10/7/2010 |
| Q: If you were going to shoot a fish under water with a bow and arrow while standing on a rock, how ... A: As the light from the fish reaches the interface between the water and the air the direction of the ... | |
| Physics question- a concept | 10/7/2010 |
| Q: If I wanted to throw a football while I'm running without changing my velocity, would it be ... A: It would be possible, but you would have to throw the ball at a very steep angle so that it would ... | |
| physics | 10/6/2010 |
| Q: a 1.0 kg box is pulled along a horizontal wooden plank by a 62 Newton force that acts parallel to ... A: This is a typical Newton's 2nd Law problem. The first step will be to make the "free body" diagram ... | |
| physics | 10/6/2010 |
| Q: how much force must be applied to accelerate a 15 kg stone straight up at 12m/s square A: To accelerate a stone straight up will require a force capable of doing 2 things; lifting the object ... | |
| Fly on a train. | 10/5/2010 |
| Q: I understand that if I was standing on a moving train and I jump I would not move back as the ... A: The train is moving, the air within the train is moving and the fly is flying in the air contained ... | |
| kirchoff's laws | 10/4/2010 |
| Q: Sir plz tell me while appling Kirchoff's voltage law on a circuit havin two loops then direction of ... A: When the currents through the common branch are in the same direction you will add the currents ... | |
| free fall acceleration | 10/4/2010 |
| Q: so i completely don't understand how to solve for free fall, like A ball is thrown vertically ... A: All kinematics problems in one dimension involve 6 variables [Do, Df, Vo, Vf, a and t] and 2 ... | |
| work | 10/3/2010 |
| Q: when golfing, i pull my bag on a cart and my friend carries his. assuming we hit in exactly the ... A: The person pulling the golf cart does more work! Why? Because the person pulling has to: 1. Lift the ... | |
| physics | 10/3/2010 |
| Q: From the top of the building 85.0 m tall a ball is dropped . At the same time another ball is thrown ... A: To solve this problem set up 2 separate kinematics problems: one for the first ball and another for ... | |
| Mechanics, using Newton's Laws, Kleppner & Kolenkow | 10/1/2010 |
| Q: Regarding 2.19 from above textbook, image available here: ... A: I agree with most of your qualitative statements but not with your resulting equations. The force ... | |
| physics | 9/29/2010 |
| Q: You are rushing to the train station to catch your morning commute. The train leaves the train ... A: All kinematics problems can be solved in essentially the same way! First, identify as many of the 6 ... | |
| PHYSICS | 9/28/2010 |
| Q: A Stack Of Books Rests On A Level Frictionless Surface. An Unknown Force F Acts On The Stack, And It ... A: To solve this problem apply Newton's 2nd Law (F=m*a) twice; once with the original load and again ... | |
| physics | 9/27/2010 |
| Q: what's the minimum stopping distance for a car traveling at an initial velocity of v, if the ... A: This is a Newton's 2nd Law problem where the sum of the external forces SF will be equal to the ... | |
| combining forces | 9/27/2010 |
| Q: I'm stuck with this question. This is what I understand, not sure if it is correct. Since a force ... A: I wouldn't think so. A problem stating that a force F is being applied to the right would seem to be ... | |
| Conservation of energy | 9/26/2010 |
| Q: this is a general question, I hope you don't mind if I'm a little vague on the details. I remember ... A: Systems will, as far as we know, tend to move to their lowest energy point if conditions permit. ... | |
| Conversions | 9/26/2010 |
| Q: 1. How much gasoline does a 10,000 watt generator use per hour assuming 1 gallon of gas contains ... A: 1. A 10,000 watt generator will generate an output of 10,000 Joules of energy each second. Since ... | |
| Force | 9/25/2010 |
| Q: A person is holding a 5-kg briefcase stationary while traveling in an elevator. Determine the ... A: As long as the elevator is moving with a constant velocity [that is it is NOT accelerating] the ... | |
| What happens when we approach a mirage? | 9/23/2010 |
| Q: What happens when we approach a mirage? Does it disappear? A: It depends on what you mean by a mirage! If you are referring to the fact that when you are walking ... | |
| Average velocity | 9/23/2010 |
| Q: A car looking for parking moves 275 m east in a straight line, then takes a left turn and covers ... A: Because displacement is a vector quantity and since the two given displacements are perpendicular to ... | |
| MPV | 9/22/2010 |
| Q: what happens to the fraction of molecules or atoms with most probable velocity in a closed system ... A: Raising the temperature of a gas increases the average linear kinetic energy of the molecules of ... | |
| speed and acceleration | 9/21/2010 |
| Q: a stone falls from a height of 40.0 m. find its speed A: Assuming that you are looking for the speed as the stone strikes the ground, this is a standard one ... | |
| Friction | 9/20/2010 |
| Q: when brakes are applied in a car, two brake shoes of inner radius 'a' and outer radius 'b' press ... A: Torque will be equal to the product of the force and the perpendicular distance to the center of ... | |
| Translational Equilibrium | 9/18/2010 |
| Q: A gong is suspended by two ropes, one makes an angle of 25 degrees with the vertical and is under ... A: The horizontal components of the tensions in these two ropes must be equal as long as the gong is ... | |
| motiom | 9/16/2010 |
| Q: a box weighing 100 N is suspende by a string . if it is applied a froce of 50 N what angle is made ... A: When you add the additional mass this problem becomes a Newton's 2nd Law problem where sum of the ... | |
| weight vs incline | 9/15/2010 |
| Q: I am training for a strongman competition in which on of the events is to pull a firetruck ... A: When you pull the truck up an incline you need to overcome two different forces: the frictional ... | |
| physics questions | 9/15/2010 |
| Q: this is my first time asking a question on here. I have 2 questions I've been struggling with all ... A: 1) For each football player the graph of the displacement-time graph would be an upward curving ... | |
| motiom | 9/14/2010 |
| Q: a box weighing 100 N is suspende by a string . if it is applied a froce of 50 N what angle is made ... A: Assuming that the force Fa is applied horizontally, the angle between the string and the vertical ... | |
| Catching a train | 9/14/2010 |
| Q: I found a similar question on one of your homework sheets to one that has been puzzling me and here ... A: In this problem a graph of displacement vs time for the accelerating train will be an upwards ... | |
| kinematics | 9/13/2010 |
| Q: I can't understand this problem please help me. thnks.Approximately 0.1% of the bacteria in the ... A: Despite the context of this question it is, none the less, a straightforward kinematics problem! All ... | |
| Physics | 9/12/2010 |
| Q: i am a college student and right now i am taking a physics class, i have no idea whats going on in ... A: I will answer your questions but I am much more concerned about your statement that "I have no idea ... | |
| atoms, molecules | 9/11/2010 |
| Q: I am writing a book in which a college student in modern times gets to look through a new microscope ... A: You have asked quite a bit here! Yes matter is mostly empty space if you mean by "empty" the absence ... | |
| physics | 9/10/2010 |
| Q: A truck of mass 2100kg is raised using a jackscrew having a pitch of 7.1mm and a handle radius of ... A: To lift a truck which has a mass of 2100 kg would require a force equal to the truck's weight Fg: ... | |
| Area of Semicircle | 9/9/2010 |
| Q: A uniform field is parallel to the axis of a hollow hemisphere (basically 3D semicircle), What is ... A: Assuming that the electric field is uniform and parallel to the symmetry axis of the hemisphere the ... | |
| teacher | 8/16/2010 |
| Q: What is Higgs boson A: The Higgs Boson is the as yet undetected particle that is believed to be responsible for the ... | |
| electrostatic | 8/15/2010 |
| Q: A charge +Q is distributed uniformly on a ring of radius a which lies in the plane z = 0. The ring ... A: Electric potential at a point is given by V=k*q/R. The resulting potential at the origin due to the ... | |
| Engineering Science | 8/14/2010 |
| Q: we have p, q and r be three vector forces, Where p = 4i+ j – 2k, q = 3i – 2j + k and r = i – 2k. ... A: First let me note that: ixj=k jxi=-k jxk=i kxj=-i kxi=j ixk=-j (p-2q) x r = -10i -8j -5k ... | |
| average velocity | 8/12/2010 |
| Q: A car travels 35km west, 90km north in two hours. What is its average velocity? A: Average velocity is equal to the displacement dD divided by the time dT: Vave=dD/dT Since the car ... | |
| electrostatics | 8/9/2010 |
| Q: how do i find the magnitude and direction of the force on a charge due to numerous other charges by ... A: The force exerted on a charge q1 sitting is an area where there are other charged particles present ... | |
| physics | 8/8/2010 |
| Q: what happens to the speed if we drop a short conductor between two magnetic poles? A: Nothing! [Other than the fact that a small potential difference will be induced between the ends of ... | |
| Black Holes | 8/7/2010 |
| Q: What would happen if two black holes were to collide? Both of them have an infinite singularity at ... A: The idea that each black hole has a singularity at the center is primarily an artifact of the ... | |
| physics | 8/7/2010 |
| Q: in a conductor all electrons have same mass and experience same force due to electric field then why ... A: The drift velocity of electrons through a wire results because the moving electrons collide with the ... | |
| Engineerinf Science | 8/6/2010 |
| Q: Can YOu Please help me with question below? A sinusoidal AC is specified by the equation, ... A: a) The coefficient of the sine function will be the peak current since the sine function varies ... | |
| Physics | 8/5/2010 |
| Q: why would a soccer ball bounce higher on harder surfaces ? why would a soccer ball not bounce as ... A: It is not so much a hard surface as it is a surface which converts the energy of the incoming ball ... | |
| Strings | 8/4/2010 |
| Q: A child's toy consists of a bat of mass 0.12 kg attached to a small ball of mass 0.03 kg by a light ... A: First, the fact that there are two toys is incidental due to the symmetry of the situation. I will, ... | |
| Eletricity | 8/3/2010 |
| Q: What is electromagnetic field and wave? What is inside the magnetic for which it show magnetism? A: Magnetism is a relativistic effect! As current flow through a wire the moving electrons are measured ... | |
| Why ? Why ? Why ? | 8/1/2010 |
| Q: Why can't physicists get a grip on the absolute truth of EinsteinGravity.com ? Please be specific. ... A: The minute ANYONE uses the words ABSOLUTE TRUTH you have lost the respect and attention of virtually ... | |
| help with planet acceleration | 7/28/2010 |
| Q: 7/25/10 Hi-I'm helping a friend with a question. I'm not asking you to solve it-I'm asking you to ... A: I do not agree on the acceleration of the Sun. The centripetal acceleration of the Sun will depend ... | |
| help with planet acceleration | 7/28/2010 |
| Q: 7/25/10 Hi-I'm helping a friend with a question. I'm not asking you to solve it-I'm asking you to ... A: The first problem is that the mass of Jupiter is mJ=1.9 x 10^27 kg The resulting gravitational force ... | |
| help with planet acceleration | 7/25/2010 |
| Q: 7/25/10 Hi-I'm helping a friend with a question. I'm not asking you to solve it-I'm asking you to ... A: Interestingly, there are two entirely independent ways to solve this problem; using kinematics and ... | |
| physics | 7/24/2010 |
| Q: James,how do i figure out the distance to impact when i let go of a rope swing into the water? For ... A: The first step is to determine the height at both the beginning and the end. If the rope is pulled ... | |
| Engineering Science | 7/23/2010 |
| Q: Can you please help me out, I cannot solve this problem it is very difficult A coiled Hookean ... A: i) To find the spring constant divide the force applied to the spring by the resulting change in ... | |
| help | 7/23/2010 |
| Q: 9000kg railroad car moving at 3m/s strikes a stationary 5000kg railroad car,what is the kinetic ... A: Kinetic energy is given by: KE=1/2*m*v^2=1/2*9000*3^2=40,500J Momentum is given by: ... | |
| sound waves | 7/22/2010 |
| Q: what song do you need to push a book over with some speakers A: This is just not something that could happen under m normal circumstances. A sonic boom might work, ... | |
| physics | 7/21/2010 |
| Q: what is the maximum possible value of the slope of a v versus t curve for a car released from rest ... A: Since the slope of a velocity-time graph is equal to the acceleration ... | |
| Physics | 7/20/2010 |
| Q: Please can you explain how a small loss of intensity (of light)occurs after reflection between two ... A: The process involved in reflecting light from a mirror is NOT 100% efficient and some energy is such ... | |
| Newton's law of motion' problem | 7/13/2010 |
| Q: I am currently stuck in this problem: The lower chamber of the heart, (the left ventricle) pumps ... A: The 0.2 seconds is the time interval during which the blood is accelerating. If the final velocity ... | |
| Physics | 7/12/2010 |
| Q: A 533-N person stands on a uniform board of weight 113 N and length of 8.3 m. The board is supported ... A: For a system to be at equilibrium [meaning that there are no accelerations] two conditions must be ... | |
| Elastic collisions | 7/11/2010 |
| Q: The 176-g head of a golf club is moving at 45 m/s when it strikes a 46-g golf ball and sends it off ... A: This is a problem using the concept of momentum conservation where momentum is equal to the product ... | |
| Physics - Horizontal Acceleration | 7/8/2010 |
| Q: Two forces f1 and f2 act on the 7kg block. The magnitudes of the forces are f1=59N and f2=33N what ... A: Using Newton's 2nd Law: SF=m*a where SF is the vector sum of the forces acting on the mass m. If the ... | |
| Significant - units | 7/2/2010 |
| Q: How do i know when to put an accuracy of significant figures (respective to their units such as Kg ... A: The position of the decimal really doesn't usually matter. when you multiply two numbers your answer ... | |
| infinity | 6/29/2010 |
| Q: Can their be infinitely big but not infinitely small ?? A: This question is more opinion than knowledge. That said, it is my opinion that neither infinity is ... | |
| Significant Figures | 6/28/2010 |
| Q: When we a convert a unit to its cubic unit like cm to cm^3 how do we deal with significant figures? ... A: According to the rule of significant digits when you multiply the number of significant digits in ... | |
| physics | 6/27/2010 |
| Q: Cathy takes the bus home from work.In her hand she holds a 2.0 kg cake boox, tied together with a ... A: 1) According to Newton's 2nd Law the sum of the forces acting on an object will be equal to the ... | |
| Crossing Ships | 6/26/2010 |
| Q: How does one calculate the amount if time two ships will be next to each other when traveling in ... A: As the two ships pass one another from bow to bow until they are stern to stern the two boats need ... | |
| physics | 6/26/2010 |
| Q: Peter and John are playing a game of tug-of-war on a frictionless, icy surface. Peter weighs 539N ... A: First of all, the masses of Peter m1 and John m2 will be: m1=539N/9.8N/kg=55.0kg and ... | |
| Time, Speed and Distance | 6/25/2010 |
| Q: Firstly, I am not requesting you to solve a text book problem. In fact, I could not really ... A: The problem is that you are assuming that the times of the journey traveled at each speed are the ... | |
| Physics | 6/24/2010 |
| Q: A uniform sphere of mass 1.8 kg and radius12 cm is rolling from the top of an incline plane. If the ... A: 1) The height of the incline will equal the length of the incline multiplied by the sin of the ... | |
| physics | 6/23/2010 |
| Q: IF I WANT TO DECLINE A 50 KG BOX FROM THE HEIGHT OF 18 FT. WHAT SLOPE SHOULD I GIVE SO THAT THE BOX ... A: You would want the box to slide down the incline at a constant speed. To do so the opposing forces ... | |
| physics | 6/20/2010 |
| Q: 1) An object that weighs 150.0N resets on a flat surface inclined at 150 degree. A force of 80N ... A: Assuming that the incline angle is 15 degrees instead of 150 degrees, the force acting up the ... | |
| Wheatstone bridge | 6/20/2010 |
| Q: Sir, can we remove the Galvanometer when the balance point has been reached, in the Wheatstone's ... A: If the bridge is "balance" removing the galvanometer will have no effect whatsoever since when the ... | |
| Physical Science | 6/19/2010 |
| Q: A box with a mass of 4.5kg is pushed along a horizontal surface at a sonstant velocity by a force of ... A: Since the box is being pushed along the horizontal surface at a constant speed the system is a ... | |
| impact-physics | 6/18/2010 |
| Q: "A 15 kN vehicle at 80kmph and 20 degrees angle of impact strikes a crash barrier. How do i ... A: To calculate the force on the barrier use the impulse equation to calculate the force required to ... | |
| impact-physics | 6/18/2010 |
| Q: A 15 kN vehicle at 80kmph and 20 degrees angle of impact strikes a crash barrier. How do i calculate ... A: You need to know more information! Specifically, you need to know either the time interval over ... | |
| Dynamic Systems | 6/16/2010 |
| Q: Please help get me started. I've drawn a diagram and put the forces on. I think I need to work out ... A: Using energy conservation! The total energy at the beginning of the problem is all gravitational. As ... | |
| Engineering science question. | 6/15/2010 |
| Q: Can you please assist with the following problem: a Canon is fired horizontally at a velocity of ... A: Since the ball leaves from a point 20 meters above the ground with no initial vertical velocity the ... | |
| vacuum technology | 6/14/2010 |
| Q: I was hoping you could help my brother and I with an argument we have regarding vacuum technology. ... A: The suction of a vacuum hose depends on both the length and diameter of the hose. Roughly speaking, ... | |
| water pipe pressure/volume question | 6/13/2010 |
| Q: We are scratching our heads about our private community water system. We've found that over the ... A: If you increase the diameter of the pipe by even a small amount you will increase the flow rate ... | |
| magnetic field | 6/13/2010 |
| Q: A 10-cm-long wire is pulled along a U-shaped conducting rail in a perpendicular magnetic field. The ... A: 1) Since power is equal to: P=I^2*R you can find the currnt: I=sqrt(P/R)=sqrt(4/0.2)=sqrt(20) 2) Now ... | |
| physics: sound and wavelengths | 6/12/2010 |
| Q: If sound has a wavelength and the higher the pitch of the sound the shorter the wavelength, then ... A: It is true that as the frequency of a sound increases the wavelength decreases. And as frequency ... | |
| waves | 6/10/2010 |
| Q: ok so how do you find the path difference and if it is destructive or constructive A: If we assume that two waves are initially in the same place and with the same phase, whether or not ... | |
| Physics question | 6/9/2010 |
| Q: 15 clowns are late to a party. They jump into their sporty coupe and start driving. Eventually they ... A: This is a Newton's 2nd Law problem where the sum of the forces acting on the car is equal to the ... | |
| physics | 6/9/2010 |
| Q: A fire fighter climbs up a 10.0m ladder leaning against a vertical wall. The ladder makes an angle ... A: The ladder leaning against the wall forms a right triangle where e height of the wall is the ... | |
| Architecture | 6/5/2010 |
| Q: If we throw continuous water on concrete building which is kept in the air direction, the outside ... A: Water cools in 2 different ways: it will cool if the temperature is less than the temperature of the ... | |
| Conservation of momentum | 6/5/2010 |
| Q: Here's something that somebody asked a while back, but I haven't been able to quite get it right. ... A: The problem is that you are assuming that the first object has stopped in the collision! Here is the ... | |
| physics | 6/4/2010 |
| Q: Your question was A helium-filled balloon rises upward, at a rate for 0.7 m/s, to a height of 20 m ... A: (a) If the balloon is rising at 0.7m/s while the wind blows east at 1.5 m/s the velocity of the ... | |
| physics | 6/4/2010 |
| Q: Question A car starts from rest and accelerates uniformly at a rate of 4.0 m/s^2 East. At the same ... A: (a) If the car accelerates east at 4.0m/s^2 for 10.0 seconds it moves: Dc=1/2*4*10^2=200m (b) Since ... | |
| Electromagnetic Induction | 6/3/2010 |
| Q: How fast would a metalic airplane with a 25 m wingspan have to fly through the vertical 5.6 x 10-8 T ... A: The potential difference generated across the length of a wire moving perpendicularly to a magnetic ... | |
| Physics | 6/2/2010 |
| Q: To measure the speed of light, Fizeau used a rotating disk with equally spaced holes through which ... A: If the distance to the distant mirror is 18000 meters away, the round trip time can be determined by ... | |
| relativistic addition of velocities | 5/31/2010 |
| Q: james, can you explain to me why we must use -0.42c in the relativistic addition of velocities ... A: The relative speed between two such objects moving through space is given by: ... | |
| torque,equilibrium | 5/29/2010 |
| Q: (1) can we do it?if not then why? with our nose touching the end of the door.put our feet astride ... A: In order for you to do either of these things opposite torques acting about your center of mass must ... | |
| Learning Physics | 5/27/2010 |
| Q: Do you mind telling me a good way how to learn physics(i.e reading textbook, teaching people)? How ... A: Each person learns in a different way. The most important part of learning physics is understanding ... | |
| physics | 5/26/2010 |
| Q: a bowling ball traveling 2 meters per second and has a kinetic energy of 12 joules, what is mass of ... A: The total kinetic energy of a rolling ball is equal to the sum of the rotational kinetic energy plus ... | |
| mechanical principles | 5/25/2010 |
| Q: a pile driver of mass 162kg falls freely through a distance of 4.1m to strike a pile of mass 393kg ... A: This is fundamentally an energy conservation problem. The initial gravitational energy of the pile ... | |
| Work Energy Theorem | 5/24/2010 |
| Q: WET is derived from Energy conservation,right? I know I can do all the WET problems using enery ... A: 1) The Work Energy Theorem essentially says that if any external work is done by or on an otherwise ... | |
| Understanding physics | 5/23/2010 |
| Q: I'm a student and i need some advice regarding learning physics. I have a lot of difficulty doing ... A: Below is an example of the thought processes needed to solve a typical physics mechanics problem. ... | |
| Electricity | 5/22/2010 |
| Q: I'm a 12th grade student.I'm confused a lot about electricity and it's hard to imagine the flow of ... A: 1. For electrostatics it is entirely possible for the potential to be nonzero when the electric ... | |
| Electricity and Magnetism | 5/21/2010 |
| Q: A three-way lightbulb produces 5W, 10W and 15W, connected to a 12V power supply. The bulb contains 2 ... A: a) Connect both filaments in parallel with each other with a single throw switch is series with each ... | |
| High Amp Vs High Freq | 5/21/2010 |
| Q: My question is Can less no. of photons having high energy can compensate high no. of photons having ... A: Light waves do not really behave in the ways that you are suggesting. Light waves are NOT exactly ... | |
| Doubt | 5/20/2010 |
| Q: A person is sitting in a car that travels with constant velocity. He throws a ball verticall ... A: As the car moves forward the ball in your hands also moves forward. I the car is moving at 30 mph ... | |
| Understanding physics | 5/19/2010 |
| Q: I'm a student and i need some advice regarding learning physics. I have a lot of difficulty doing ... A: The fundamental thing you have to learn is that it is the concepts that are most important! If you ... | |
| Electricity | 5/19/2010 |
| Q: I'm a 12th grade student.I'm confused a lot about electricity and it's hard to imagine the flow of ... A: 1. Interactions between the electrons flowing through a wire and the matter from which the wire is ... | |
| Motion | 5/18/2010 |
| Q: Define uniform and non uniform motion? Give examples. A: In uniform motion the speed and direction of motion of an object is constant. If both of these ... | |
| High Amp Vs High Freq | 5/18/2010 |
| Q: My question is Can less no. of photons having high energy can compensate high no. of photons having ... A: That doesn't change my answer at all! The energy content of light is transferred in small packets or ... | |
| question | 5/17/2010 |
| Q: A 2.5kg block is suspended vertically from a spring, which stretches .2 meters from its original ... A: When you connect springs in series the total spring constant is related to the separate spring ... | |
| Water Level | 5/16/2010 |
| Q: We all know the saying that "water seeks its own level". What physics principal is it called?? A: Ultimately what happens is that in a container open to the atmosphere the pressure exerted at any ... | |
| High Amp Vs High Freq | 5/15/2010 |
| Q: My question is Can less no. of photons having high energy can compensate high no. of photons having ... A: Depends on the context of your question. In the case of the Photoelectric Effect [for which Einstein ... | |
| Refractive index | 5/14/2010 |
| Q: *Is it possible to have refractive index less than 1?Why and why not? *If there is any medium which ... A: Normal materials will always have an index of refraction greater than or equal to 1. If a material ... | |
| static electricity | 5/14/2010 |
| Q: When a man touches the metal bar when using a treadmill he occasionally gets a small shock. Why ... A: The small shock occurs because of the accumulation of charge - and this takes time. It also depends ... | |
| Physics - Inclines | 5/12/2010 |
| Q: I need help with thisA car, with a mass of 1100kg, can accelerate on a level road from rest to 21 ... A: First calculate the force needed to accelerate the car at the given rate using Newton's 2nd Law: ... | |
| Atoms | 5/12/2010 |
| Q: has what we know about atoms harmed humankind? like the atomic bomb? A: This is very difficult to respond to! We are made of atoms! Everything we eat or breath is made of ... | |
| specific heat | 5/11/2010 |
| Q: Why specific heat of diatomic molecule is greater than mono atomic molecule? A: The answer to this question rests primarily on the fact that a diatomic molecule has many other ways ... | |
| velocity | 5/10/2010 |
| Q: If a ball that is freely falling has attained a velocity of 19.6m/s after two seconds, what is its ... A: If the ball was moving at 19.6 m/s after 2 seconds the acceleration of the ball must have been: ... | |
| How do I find the center of gravity using this data I collected? | 5/10/2010 |
| Q: In a lab in my physics class, we were supposed to find the CG of my physics teacher. My partner and ... A: Try this approach! The center of mass of the board multiplied by the mass of the board plus the ... | |
| Particle acceleration | 5/9/2010 |
| Q: I've just finished watching two multi-episode introductory courses on physics (Goodstein's & ... A: First of all, in general, we do not accelerate a single particle but rather we accelerate bunches of ... | |
| Physics | 5/8/2010 |
| Q: find the density of a solid 1.5 kg paperweight you submerge it in a water tank and note that the ... A: Density is equal to the mass of an object divided by the object's volume. Since the submerged object ... | |
| i have a question. | 5/8/2010 |
| Q: What could cause a force of impact? A: When an object is in motion it contains kinetic energy [the ability of a moving object to do work ... | |
| physics C, mechanichs | 5/4/2010 |
| Q: a highway curve that has a radius of curvature of 100 meters is banked at an angle of 15 degrees. ... A: In the first case let’s assume that the curve is frictionless [much like the conditions that might ... | |
| Physics | 5/1/2010 |
| Q: How come in a plane mirror,the image is virtual but the imaginary light rays do not meet at an ... A: But the imaginary light rays DO meet behind the mirror! The light Ray drawn to the vertex of the ... | |
| Electric Field Intensity (E) | 5/1/2010 |
| Q: I've a lot of Qs regarding E.Please help me kind sir and stuck in a mire of confusion. 1)Consider a ... A: 1) The electric field inside a neutral conducting spherical shell will be exactly zero as long as ... | |
| Moment of inertia | 4/30/2010 |
| Q: A 25.7 kg block (m1) is on a horizontal surface, connected to a 6.30 kg block (m2) by a massless ... A: To solve this problem you will need to apply Newton's 2nd Law 3 times! Once for each mass and once ... | |
| Mechanics | 4/29/2010 |
| Q: sir, the question is in the image itself A: As this frictionless incline is accelerated to the right Newton's 1st Law applies to the vertical ... | |
| Electric potential | 4/29/2010 |
| Q: Sir why is mathematically Electric potential not analogous to Gravitational potential? I've a Q ... A: But it is as long as you realize that unlike the gravitational force, the electrostatic force can be ... | |
| capacitors | 4/28/2010 |
| Q: my question is as follows: A 400(micro)Farad capacitor is charged so that the voltage across its ... A: The capacitance of a parallel plate capacitor is given by: C=Q/V Using this information we can ... | |
| i need help with gratings | 4/27/2010 |
| Q: A diffraction grating produces a first-order bright fringe that is 0.0904 m away from the central ... A: The equation relating the wavelength of the light illuminating a diffraction grating and the ... | |
| i need help with photons | 4/27/2010 |
| Q: The maximum wavelength for which an electromagnetic wave can eject electrons from a platinum surface ... A: Since the 196 nm light is the least energetic light capable of freeing an electron from the given ... | |
| Physcis Momentum | 4/26/2010 |
| Q: I need a help ASAP in one problem. Due is 5:00 PM, April 26. I have some idea but not sure is right. ... A: a. Puck 1 will be to the right of the dotted line. Since the accelerations of both pucks are the ... | |
| temperature of mixture | 4/26/2010 |
| Q: sir; how to find the resultant temperature of mixtre of given quantity of ice and boiling water???? A: The problem is a somewhat annoying problem to solve since as many as 5 calculations will have to be ... | |
| molten iron | 4/25/2010 |
| Q: eric A: It will no longer be ferromagnetic! When you heat any ferromagnetic material [iron, cobalt, nickel] ... | |
| Flux | 4/24/2010 |
| Q: Sir, Electric Flux is the no. of electric lines present in a unit area, right?It can be either +ve ... A: I think that you are taking the idea of electrostatic flux too literally. The "lines of flux" are ... | |
| Physics | 4/23/2010 |
| Q: An elastic cord has an unextended length of 13.0 cm. One end of the cord is attached to a fixed ... A: Actually, I suspect that this question is flawed! From the way the question is stated it seems to me ... | |
| Question about a satellite orbiting Mars | 4/23/2010 |
| Q: Although the Constellation Program which planned to send humans back to the Moon and on to Mars ... A: In geosynchronous orbit the orbital period of the satellite must match the rotational period of the ... | |
| MA of inclined plane | 4/22/2010 |
| Q: Sir: How can i calculate MA of inlined plane in lab?is it calculated by dividing total length of ... A: The ideal mechanical advantage IMA of an inclined plane will be equal to the length of the incline ... | |
| Physics | 4/20/2010 |
| Q: If we were to drop a cart to the ground from a height of 3 meters, how long will it take to land on ... A: Thus is a standard kinematics problem. First identify each of the possible kinematics variables: ... | |
| Four Wheel Drive | 4/19/2010 |
| Q: my roommate and I were having a conversation on four wheel drive vs two. So coming from someone with ... A: The primary difference is that in 4 wheel drive every wheel is capable of providing friction for ... | |
| electricity | 4/19/2010 |
| Q: if a circuit containing 1 meter of wire and three light bulbs was changed to 0.75 meter of wire and ... A: Assuming that all of the components are identical . . . Ordinarily changing the length of the wire ... | |
| Time Dilation - This is a bit tricky for me - Please Explain? | 4/18/2010 |
| Q: Twins who are 19 years of age leave the eath and travel to a distant planet 12 light years away and ... A: The time to reach and return from the distant planet in the rest frame can be determined by ... | |
| Physics - forces problem | 4/17/2010 |
| Q: A 2.0 kg frictionless puck is at rest on a level table. It is pushed straight north with a constant ... A: This is a standard kinematics equation. First identify as many of the 6 kinematics variable as ... | |
| Electric Field | 4/15/2010 |
| Q: An electric field of approximately +100 V/m is often observed near the surface of the Earth. If this ... A: a. To determine the total electric flux at the surface of the earth multiply the field intensity by ... | |
| Vertical Acceleration | 4/14/2010 |
| Q: I need help with these questions (particularly the equations used to solve) A 5kg ball is released ... A: A. The initial vertical velocity will be 0.0 m/s. [The ball is not moving vertically as it is ... | |
| Physics-Kinematics | 3/23/2010 |
| Q: A boat travels at 10.3 km/h relative to the water aims straight for the opposite bank of a 33.1 m ... A: First find the time to cross the river by dividing the width of the river by the speed of the boat ... | |
| magnetic | 3/20/2010 |
| Q: Using current loops,explain the difference between a paramagnetic and a ferromagnetic material. A: Paramagnetic materials and ferromagnetic materials both have unpaired electrons in common. In ... | |
| physics 111 (algebra based physics) | 3/19/2010 |
| Q: My name is Shawn. This is my third year in college and i have never taken physics before this ... A: In order to push this carton up the incline at a constant the applied force Fa must do two things: ... | |
| Conservation of Energy | 3/15/2010 |
| Q: A 0.40kg ball is thrown with a speed of 9.5m/s at an upward angle of 37 degrees. a)what its speed at ... A: If you throw the ball with a velocity of 9.5m/s at an angle of 37 degrees above the horizontal, the ... | |
| energy | 3/11/2010 |
| Q: I'm stuck on this problem, i need to know step by step please. A pulley system is used to raise a ... A: If the output force is 100kg*10N/kg=1000N [assuming the acceleration of gravity to be 10m/s^2] while ... | |
| (physics) acceleration | 3/10/2010 |
| Q: What force is required to accelerate a 6 kg bowling ball at 2 m/s squared? (UPWARD) A: In order to accelerate an object upward you need to do two things: overcome the force of gravity and ... | |
| electric field | 3/9/2010 |
| Q: electric field lines represent the field at various locations. except in very special cases, they do ... A: The fact that the particle is moving has nothing to do with whether or not the particle feels a ... | |
| modern physics | 3/8/2010 |
| Q: respected teacher, i will feel obliged if you answer my question Why we write wave equations to ... A: According to quantum mechanics the wave function is related to the probability that at particular ... | |
| electric field | 3/8/2010 |
| Q: electric field lines represent the field at various locations. except in very special cases, they do ... A: In any case the electric field lines do not illustrate the path of a charged particle through a ... | |
| Electricity | 3/7/2010 |
| Q: Electric current deals with flow of charges. But, What is electric field? How the electrons travel ... A: An electric field is an area of space where if a charged particle is placed in that field it will ... | |
| Special Relativity | 3/6/2010 |
| Q: I am studying through a correspondence university so i do not attend lectures. I know you probably ... A: The time dilation equation relates the time passage in the moving frame of reference T=0.5yr with ... | |
| capacitor | 3/5/2010 |
| Q: how capacitor used to remove noise in electronic circits? A: When unintended electrical spikes occur in a circuit, a properly placed capacitor can temporarily ... | |
| sound and thunder | 3/3/2010 |
| Q: 1. A common statement is that when you see a lightning flash, and count the number of seconds until ... A: The point here is that, for all practical purposes, the speed of light is instantaneous while the ... | |
| Physics - Dynamics | 3/2/2010 |
| Q: 1. With the engine working at constant full power, the car's acceleration decreases as it goes ... A: 1. The issue here is turbulent air flow. In general the frictional force of the air on a moving car ... | |
| electronics | 2/28/2010 |
| Q: respedted sir, of what physical law is The equation of continuity a mathematical statement ? A: The law of continuity is a statement of mass conservation! The amount of matter flowing into a pipe ... | |
| hello, can you help me with this | 2/27/2010 |
| Q: A rectangular loop of wire is moving toward the bottom of the page with a speed of 0.023 m/s (see ... A: The rate of change of magnetic flux will be dphi/dt=d[B*A]/dt=d[B*x*y]/dt=B*x*dy/dt=b*x*Vy where ... | |
| Gravity, mass and force | 2/24/2010 |
| Q: If I have two metal balls which are the same sizes but one is 20 kg and the other is 5 kg. If I drop ... A: IF you ignore the effects of air friction they will both hit the ground at the same time. If air ... | |
| physics help please its driving me crazy | 2/24/2010 |
| Q: The four masses shown in the figure are connected by massless, rigid rods. a.Find the coordinates ... A: a. To find the center of mass in the x direction multiply each separate mass by its x coordinate and ... | |
| Electric Circuit Analysis | 2/22/2010 |
| Q: First off, I want to tell you that this is not a homework problem. It was, but the assignment is ... A: Tough problem to do with text only! I assumed that the top left loop had a clockwise current I1, the ... | |
| electronics | 2/21/2010 |
| Q: why it is that in series connection current remains constant but in parallel connection voltage ... A: Current is a measure of matter! Whatever current enters a series circuit must exit that same ... | |
| drawing graphs | 2/20/2010 |
| Q: tom is driving to the soccer field. he starts from rest and speeds up to 20m/s-1 in 5 seconds. the ... A: The velocity-time graph should be a straight diagonal line between 0-5 seconds with a slope of ... | |
| Galilean/Newtonian Relativity | 2/19/2010 |
| Q: A person in an elevator drops a ball of mass m from rest a height h above the elevator floor. The ... A: Treat this as a normal one dimensional kinematics problem. First identify as many of the kinematics ... | |
| physics | 2/18/2010 |
| Q: what forece are at work when an object is spun in a circle? A: Depends! In any case, some specific force will be required to cause the object to move in a circular ... | |
| physics | 2/17/2010 |
| Q: A 2.0 kg box rests on a plank that is inclined at an angle of degrees above the horizontal. The ... A: You don't give the angle, but the maximum force that the spring can apply up the incline will be ... | |
| physics | 2/16/2010 |
| Q: Theories, and basically all of science is full of assumptions and over-simplified versions of ... A: I think you really underestimate scientists in general and physicists in particular! Models are used ... | |
| gravity, speed | 2/15/2010 |
| Q: A girl is standing at the edge of the Grand Canyon. She throws one ball straight up and another she ... A: You are correct, the ball thrown up will strike the bottom of the canyon with greater velocity [only ... | |
| Gravity | 2/15/2010 |
| Q: The wave properties of gravity. I have knowledge that when two very massive objects(neutron ... A: Most physicists do believe that gravity waves exist, but we have never yet detected them! Why not? ... | |
| Electroststic Induction | 2/13/2010 |
| Q: When I bring a charged body near to a conducting body electrostatic induction occurs. How can I find ... A: Without more details all I can say is that if the charged body is positive, electrons on the ... | |
| Doppler Effect | 2/12/2010 |
| Q: I am busy with a very important physics module. Do you mind helping me out with this question. I ... A: As the observer is walking AWAY from speaker A the apparent frequency will be given by: ... | |
| Wave-particle duality | 2/12/2010 |
| Q: I have just started studying Quantum Mechanics. Consulting to book, “Quantum Mechanics” by ... A: Unfortunately, I suspect that I will not be able to help the way you would like! All that can be ... | |
| heat & thermodynamics | 2/11/2010 |
| Q: A ball of copper [Cp=.093 cal/gm C] has a mass of 125 grams and is at a temperature of 145 C. This ... A: 17. A ball of copper [cp = .093 cal/gmoC] has a mass of 125 grams and is at a temperature of 145 oC. ... | |
| Physics | 2/11/2010 |
| Q: I recently read your response to a force vector problem: If two snowcats tow a housing unit to a ... A: In order to pull the house straight ahead the components of Fa and Fb acting perpendicularly to the ... | |
| #17 on Homework #172 | 2/10/2010 |
| Q: How do you solve #17 on your homework #172? We know the answer, but all our pitiful attempts at ... A: 17. A ball of copper [cp = .093 cal/gmoC] has a mass of 125 grams and is at a temperature of 145 oC. ... | |
| Transverse waves | 2/9/2010 |
| Q: I have looked all through my textbook for a way to help me solve the following problem: The speed ... A: If the amplitude of the wave 2.0mm during one cycle a point on the string will move from crest to ... | |
| expansion in solid and liquids. lens focal length | 2/7/2010 |
| Q: would it be possible to make mercury thermometre if expansion of glass becomes more than mercury? ... A: Mercury thermometers are calibrated with this in mind! Mercury is selected because its thermal ... | |
| help | 2/7/2010 |
| Q: draw the force diagram foa block of wood resting on an inclines plane. NOTE that the wood is acted ... A: When you add a force to a force diagram every force must be real! What I mean by this is that you ... | |
| Arcemedes Principle | 2/6/2010 |
| Q: A piece of metal of unknown volume is immersed in water by means of a thread.Before lowering into ... A: For a submerged object the upward buoyancy force is equal to the volume of the displaced liquid. If ... | |
| Physics - Friction | 2/2/2010 |
| Q: A box being pushed with a force of 85N slides along the floor at a constant speed. What is the ... A: Since the box is sliding at a constant speed it is at equilibrium and opposite forces are equal. In ... | |
| question | 2/1/2010 |
| Q: You are driving down the road and hit a bump which causes your fishing tackle box to bounce out of ... A: First identify as many of the kinematics variables at possible. In this case: Do=0m [always assume ... | |
| Gas problem | 1/31/2010 |
| Q: Two moles of He gas are at 27 degrees C and a pressure of 250 kPa. If the gas is heated to 44 ... A: According to the universal gas law: P*V=N*R*T Therefore the initial volume of the gas is: ... | |
| 2D kinematics | 1/30/2010 |
| Q: A ball is launched horizontally off a table top that is 1m high. It lands 3m from the base of the ... A: First calculate the time using the vertical information: Do=1.0m, Df=0m, Vo=0m/s, Vf=?, a=-9.8m/s^2 ... | |
| physics | 1/29/2010 |
| Q: 1.) A log is floating on swiftly moving water. A stone is dropped from rest from a 70-m-high bridge ... A: This is a straightforward one dimensional kinematics problem. First find the time for the stone to ... | |
| Phyics | 1/28/2010 |
| Q: Ions with a charge of 1e (e is the charge of the electron) travel at a speed v = 4.7 times 10 to the ... A: Since the magnetic field exerted a force acting perpendicularly to the direction of motion of the ... | |
| Photoelectric Effect Related Problem | 1/28/2010 |
| Q: Monochromatic light of wavelength λ falls on Potassium surface, it is found that stopping ... A: What you want to do is to make a graph comparing the kinetic energies of the emitted photoelectrons ... | |
| resistance | 1/27/2010 |
| Q: sir I have one question. we all know that copper is a better conductor than iron. Now in text books ... A: Keep in mind that there is a lot of space within the conductor for the electrons to move. The ... | |
| Magnetic field and current generation | 1/27/2010 |
| Q: Sir, if I move a conductor such as a wire past the magnetic field of a permanent magnet, the field ... A: First, note that a current will be produced only if the conducting wire is moving perpendicularly to ... | |
| Mmm... Newton's laws, perhaps? | 1/26/2010 |
| Q: Is it Newton's law that an external compressive force applied on a tube (like an artery, I'm a ... A: When you compress the center of a tube you increase the pressure, a force per unit area. That pulse ... | |
| Physic ? Help Im lost | 1/25/2010 |
| Q: A ball is dropped on a distant planet with no atmosphere. The ball Falls a distance of 3.0 meters in ... A: Since the distance traveled by as accelerating object is proportional to the square of time, ... | |
| magnetic | 1/24/2010 |
| Q: a vertical conducting sheet is permitted to fall under the action of gravity between the poles of a ... A: Yes [assuming that the entire sheet isn't between the poles of the permanent magnet all at once]. As ... | |
| Physics | 1/24/2010 |
| Q: The click beetle can project itself vertically with an acceleration of about 400g. The beetle jumps ... A: This is a 2 part kinematics problem. 1. In the first part Do=0m [given], Df=0.0067m [given], ... | |
| help please! | 1/23/2010 |
| Q: The potential at location A is 385 V. A positively charged particle is released there from rest and ... A: If you multiply the change in potential difference by the magnitude of the charge moving between ... | |
| Motion | 1/23/2010 |
| Q: In my exam there was a question "When a train(rail)driver starts a train(diesel train) he first ... A: My guess is that by backing up first the engine develops some slack between the engine and the train ... | |
| About B-field generated by moving charge. | 1/22/2010 |
| Q: 1)When a charged particle is accelerated, does it too generate a circular magnetic field around its ... A: Any MOVING charged particle will generate a magnetic field! The generation of this field does NOT ... | |
| Recoil | 1/22/2010 |
| Q: I was out for a week while my teacher was talking about recoil, momentum conservation and stuff. I ... A: Since total momentum has to be conserved in a closed system: m1*v1+m2*v2=m1*v3+m2*v4 In this case ... | |
| Moving Charges | 1/21/2010 |
| Q: Sir, 1)Why can't a magnetic field change the kinetic energy of a charged particle? 2)Why can't an ... A: In a cyclotron the magnetic field is used to keep the moving charged particles moving in a cicular ... | |
| Moving Charges | 1/20/2010 |
| Q: Sir, 1)Why can't a magnetic field change the kinetic energy of a charged particle? 2)Why can't an ... A: 1) The magnetic force [Fm=q*VxB] acting on a moving charged particle is always exactly perpendicular ... | |
| physics | 1/18/2010 |
| Q: A child throws a ball straight down off the balcony of an apartment building at a speed of 7.5 ... A: All kinematics problems can be solved in the same way! First identify as many of the six potential ... | |
| physics | 1/17/2010 |
| Q: bullet has a much smaller mass than a one-ton car, yet, it may deliver more force when it strikes an ... A: The amount of force delivered to the target is determined in large part by the kinetic energy of the ... | |
| physics | 1/16/2010 |
| Q: A ball is thrown 125m upwards. What initial speed does the ball need to remain in the air for total ... A: All one dimensional kinematics problems can be solved in exactly the same way! First identify as ... | |
| Photoelectric effect | 1/16/2010 |
| Q: on doubling the frequency of incident radiation does the kinetic energy of emitted electrons get ... A: Actually, neither. Assume for a moment that the incoming light contains 15 eV of energy and that the ... | |
| physics | 1/15/2010 |
| Q: A bus is traveling a roadway at the base of an improperly designed road cut. Because of the geology, ... A: When a mass is sitting on an inclined plane the force tending to pull something down the incline ... | |
| Physics. Sorry wrong address | 1/14/2010 |
| Q: In a sample of seawater taken from an oil spill, an oil layer 6.0 cm thick floats on 52 cm of water. ... A: The pressure at the bottom of a depth of fluid is equal to the product of the fluid density p, the ... | |
| Conservation of Linear Momentum | 1/13/2010 |
| Q: Mr. Kovalcin, Please help me with this question. My nephew is taking AP Physics (senior in high ... A: I am using a coordinate system along the x axis with zero at the left, the initial position of the ... | |
| physics | 1/11/2010 |
| Q: f you have a charge of q=-1 microCoulomb at point A, the potential of point A is Va=2 volts, and the ... A: If the potential at point A is Va=2 Volts and the potential at point B is Vb=4.3 Volts it would take ... | |
| Effects of x-ray on vitamins & supplements | 1/9/2010 |
| Q: What are the effects of airport x-rays of vitamins, nutritional supplements and medications? A: The effect is very insignificant. The only thing that may be significantly damaged by the xray ... | |
| relation between derivatives of speed and velocity | 1/3/2010 |
| Q: This may be very basic: Consider a motion influenced only by gravity (some frictionless 2D ... A: It appears that you are confusing the difference between vector and scalar. When you are calculating ... | |
| Gasses,Temperature,velocity and pressure. | 1/3/2010 |
| Q: When the temperature of a gass is risen the kinetic energy of a gass rises. Why is that? If it's ... A: You are working under an invalid premise! The velocities will NOT be the same. The average ... | |
| optics | 1/2/2010 |
| Q: My question is why do we obtain images on screen only after all rays emerging from a point on the ... A: For images far away, such as stars, we do NOT, in fact, get an image! All we get is a point of light ... | |
| Question about phisics | 12/31/2009 |
| Q: I can't understand special theory of relativity.it has two postulates.tell me how it effect on these ... A: Basically, the two postulates are based on our observations. 1. The speed of light is the same for ... | |
| Optics | 12/30/2009 |
| Q: A small piece of wood is floating on the surface of a 2.5 meter deep lake. Where does the shadow ... A: As light travels from one medium into another the angle between the light ray and the normal to the ... | |
| optics | 12/29/2009 |
| Q: why can we see nearby objects more clearly than comparatively farther object ? ANSWER: The reality ... A: Actually, for stars this is NOT the case! Almost all stars, except the very closest, appear in ... | |
| Physics - Electrostatics | 12/29/2009 |
| Q: Two point charged objects produce an electric force on each other of 6.20x10^-2 N. What is the ... A: Since the electrostatic force between two charges is given by Fe=k*q1*q2/r^2 if you increase the ... | |
| optics | 12/28/2009 |
| Q: why can we see nearby objects more clearly than comparatively farther object ? ANSWER: The reality ... A: Because "all light from far objects" does not reach our eyes! The light from a star, as an example, ... | |
| physics | 12/27/2009 |
| Q: how banking of roads provide required centripetal force to vehicle? and if a car is moving with high ... A: Ordinarily, for a car on a level road, the source of the normal force that is responsible for ... | |
| Moment of inertia | 12/26/2009 |
| Q: I've solved quite a lot of MoI questions but now I've seen sth different.How do I find the MoI of a ... A: Assuming that you a talking about the moment of inertia around the same axis, the central axis of ... | |
| electric field of isolated metal box has a charge in center | 12/26/2009 |
| Q: The point charge Q is at the center of a metal box that is isolated, ungrounded, and uncharged. ... A: The answer is A. A. Since the box is an uncharged conductor -Q will be attracted to the interior ... | |
| optics | 12/25/2009 |
| Q: In light diffraction using single slitwhich is correct from the following ,and why?: 1- Light ... A: Diffraction of a wave around a slit will be more significant when the wavelength of the wave is long ... | |
| Braking | 12/25/2009 |
| Q: Does the time you take to slow a car using the breaks effect how much wear and tear is done to the ... A: My guess would be that stopping quickly would wear the brakes more quickly since the increased ... | |
| electric current | 12/24/2009 |
| Q: 1.What is the difference between emf and potential difference? Explain me in detail. 2.What is the ... A: There are two different kinds of potential differences: EMF's and voltage drops. An EMF is any ... | |
| nuclear force | 12/24/2009 |
| Q: 1.Why the nuclear force is a short range force, but gravity is a long range force? Why these forces ... A: 1. The nuclear force is very short in range for a very simple reason - the boson that communicates ... | |
| bandwidth | 12/23/2009 |
| Q: please tell me is there any relation between bandwidth and frequency of the signal?does higher ... A: Greater bandwidth just implies that more information can be carried on the carrier signal. For ... | |
| hydrostatic equilibrium | 12/23/2009 |
| Q: In hydrostatic equilibrium pressure of gas at the surface of the planet is equal to the weight of ... A: The pressure will remain the same; whether liquid or gas is irrelevant. For example the atmosphere ... | |
| Work Energy Theorem | 12/22/2009 |
| Q: I'm a bit confused in writing equations stating conservation of energy. Suppose a block of mass m ... A: It seems to me that your analysis is correct. If the mass started at rest at the top of the incline ... | |
| Circular motion concepts | 12/22/2009 |
| Q: 1. If a body moves with a fixed speed but changes its direction it is said to accelerate, right? So ... A: 1. When we refer to the tangential component of the acceleration of an object moving in a circular ... | |
| light | 12/20/2009 |
| Q: Will you explain shortly about refraction, diffraction, interference and polarisation of light? If ... A: Refraction - The process where a wave transfers from one medium into another frequently accompanied ... | |
| momentum and gravity | 12/20/2009 |
| Q: 1.I know that momentum = mass*velocity. But, what it means. Why we're multiplying mass and velocity. ... A: First of all you can NEVER add unlike quantities such as mass and velocity. In any case, momentum is ... | |
| momentum and gravity | 12/19/2009 |
| Q: 1.I know that momentum = mass*velocity. But, what it means. Why we're multiplying mass and velocity. ... A: 1. It is exactly what it says it is! If you multiply the mass of an object by its velocity the ... | |
| Banking of roads | 12/18/2009 |
| Q: "Sir I've been trying to figure out a situation in banking of roads i.e. the first case in this link ... A: 1. Not exactly. As a car moves down a straight road at a constant speed there is air friction ... | |
| gravity | 12/17/2009 |
| Q: Acc. due to gravity is 9.81m/s/s....when in orbit around the Earth is it still the same or less? ... A: The acceleration of gravity near a planet is given by: g=G*m/R^2 where G=6.67x10^-11 is the ... | |
| Physics - work - | 12/17/2009 |
| Q: * A girl pushes a 300 N box along the floor for a distance of 4 m. The coefficient of kinetic ... A: Work is defined to be equal to the product of the force F applied and the resulting displacement d ... | |
| kinematics | 12/16/2009 |
| Q: an elevator car whose floor to ceiling ht is 2.7m starts ascending with constant acceleration ... A: Because the elevator is accelerating upward for 2.0 seconds at 1.2m/s^2 before the bolt falls the ... | |
| Physics | 12/15/2009 |
| Q: Wile E. Coyote decides to try and catch Road Runner. He launches himslef from a cannon at a 33.7 ... A: This problem is a typical two dimensional kinematics problem - all of which can be solved in the ... | |
| Physics | 12/14/2009 |
| Q: A 70-kilogram diver jumps off a 12-meter tower and hits the water below. The diver comes to a stop ... A: The first step here is to determine the velocity of the diver as he/she reaches the water. this can ... | |
| Normal Force and Friction Force | 12/13/2009 |
| Q: A 80 N block rests on a 29° inclined plane. Determine the normal force and find the friction force ... A: When a block sits on an inclined plane it is at equilibrium. If it is at equilibrium then opposite ... | |
| Bullet train & Car | 12/7/2009 |
| Q: Why we can pour water to the cup without spill it out in a bullet train? And why we can barely ... A: Because of the much larger mass, velocity and momentum the Bullet Train will be much more stable; it ... | |
| upward pressure | 12/6/2009 |
| Q: we have a bag of cotton and iron bar each indicating a mass of 100 kg. when measured on a weighing ... A: I suppose that one could argue that the bag of cotton would weigh less because it displaces a much ... | |
| atomic radar action | 12/6/2009 |
| Q: In thinking about how radar works, what is going on at the atomic level? A: Basically all that is happening is that electrons in the material absorb the radar energy driving ... | |
| not sure? physics question | 12/5/2009 |
| Q: a student takes a meter stick w/ a mass of .5 kg and drives a nail through the 50 cm mark. the ... A: Use energy conservation! Initially the m1=2kg mass and the m2=0.020kg wad of clay are at the same ... | |
| physics... vibrations | 12/4/2009 |
| Q: A simple pendulum with a length of 2.33 m and a mass of 6.79 kg is given an initial speed of 1.46 ... A: a) The period of a simple pendulum is given by: T=2*pi*sqrt(L/g) where L=2.33m is the length of the ... | |
| Physics | 12/1/2009 |
| Q: Block A and block B are moving toward each other. Block A has a mass of 2 Kg and a velocity of 50m/s ... A: All one dimensional momentum problems between two objects can be solved in the same way! Since ... | |
| chemistry 100 | 12/1/2009 |
| Q: Suppose in the middle of a pool game, you shoot the cue ball, causing it to hit the balls on the ... A: I wouldn't say "impossible", but the probability of such an event is incredibly small! The concept ... | |
| Conservation of momentum Q | 11/30/2009 |
| Q: A dog of mass 5kg is standing on a flat boat so that he is 10m away from the shore.He walks 4m on ... A: In an isolated system [which this boat + dog approximates] the velocity of the center of mass ... | |
| Coefficient of restitution | 11/29/2009 |
| Q: A ball moving with a velocity i^(unit vector along X axis)collides with a huge wall which is at rest ... A: The coefficient of restitution relates the relative velocity of the two colliding objects after the ... | |
| some question :) | 11/28/2009 |
| Q: I have 4 question . pleaseteacher, I want the solution steps . Question : 1. A 5.0 kg object placed ... A: 1. Newton's 2nd Law problem; The sum of the external forces SF acting on a system is equal to the ... | |
| Newtonian Physics 2 | 11/27/2009 |
| Q: Re:Newtonian Physics Sit Thanks you very much for the help Sir.I'm really glad that I could ... A: The key here is that each plank does a certain amount of work on the bullet as it passes through. ... | |
| Newtonian Physics | 11/26/2009 |
| Q: I've tried this problem for like 25 times but couldn't get the correct answer, sir. 1.A bullet ... A: 1. If the bullet loses 1/nth of its velocity it will retain [(n-1)/n]^2th of its energy [since ... | |
| optical physics | 11/24/2009 |
| Q: In diffraction grating experiment using spectrometer we see violet fringe first and then ... A: The answer to this quest is caused by the fact that the two effects are entirely different and ... | |
| General Force Question | 11/22/2009 |
| Q: Why is the anti-derivative of the net Force exerted on an object equal to potential energy of the ... A: Work done is equal to the product of force and the distance through which the force is applied while ... | |
| concave mirror | 11/22/2009 |
| Q: what are some application of a concave mirror A: Concave mirrors are used for: 1. Newtonian, catadioptric and Dobsonian Reflecting telescopes 2. Long ... | |
| Physics AP homework problem, plz help! | 11/21/2009 |
| Q: a person jumps from the roof of a house 3.9 meteres high. when he strikes the ground below, he bends ... A: There are two parts to this problem: first find the time to stop, second find the required force. To ... | |
| physics | 11/21/2009 |
| Q: is insulator has a charge? A: All matter contains charge. What makes an insulator special is that the charges contained within the ... | |
| dynamics | 11/20/2009 |
| Q: can u help me in this question Steep safety ramps are built beside mountain highways to enable ... A: (a)If the acceleration of the truck is constant and if it takes 6 seconds for the truck to lose 1/2 ... | |
| Carnot Engine | 11/18/2009 |
| Q: Kovalcin, I am a student at Laurentian University studying Geology. I am in first year and in ... A: If 30% of the heat is dumped into the cold reservoir the efficiency of the process is 70% rather ... | |
| radioactivity | 11/17/2009 |
| Q: In the process of beta decay a proton transforms into a neutron according to p-----> n + ... A: The energy of the incoming proton is converted into the mass of the resulting products. Mass is NOT ... | |
| Circular Motion and Gravitational Forces | 11/16/2009 |
| Q: Early skeptics of the idea of a rotating Earth said that the fast spin of Earth would throw people ... A: Question 1 is a relative velocity question. Just add the velocity of you to the velocity of the bus! ... | |
| Physics | 11/15/2009 |
| Q: Sorry if this question has been asked before but i can't find it on the sheet. Someone jumps a hole ... A: All 2 dimensional kinematics problems can be solved in the same way. There are 6 kinematics ... | |
| Circular Motion and Gravitational Forces | 11/14/2009 |
| Q: Early skeptics of the idea of a rotating Earth said that the fast spin of Earth would throw people ... A: a) To determine the velocity of someone at the equator use the definition of velocity: v=dD/dT ... | |
| physics | 11/14/2009 |
| Q: please give me ideas for making working model on any topic of physics like light, electricity, ... A: One of the most fun projects is to make a "Rube Goldberg" machine. [Do a Google search on this ... | |
| specific heat capacity | 11/13/2009 |
| Q: if you wish to warm 100 kg of water by 18 degrees celsius for your bath, how much heat is required? ... A: The heat needed to change the temperature of a substance is given by: dQ=m*c*dt where dQ is the ... | |
| observation | 11/12/2009 |
| Q: I've been reading about the quantum and I know if you observe (interact) with what you are ... A: A full discussion would be rather lengthy but the fact is that experiments have been run where the ... | |
| electricity | 11/11/2009 |
| Q: explain why a battery of ten dry lechlanche cells each of emf 1.5volts cannot be used in place of a ... A: Electric power requires BOTH current and voltage. The current is the carrier of energy while the ... | |
| What's the principle that correlates diameter of a tube and its inner liquid pressure value? | 11/10/2009 |
| Q: What is the name of the Principle that states that for a fixed flux of liquid through a tube, the ... A: What you are looking for it the "Law of Continuity". Since a typical fluid is matter, and since ... | |
| Speed, time and and distance | 11/7/2009 |
| Q: can you please give me all the formulas for the 9th grade? and it should be about speed, time and ... A: First of all there is no such thing as "all the formulas for the 9th grade"! However, if you a ... | |
| Speed | 11/6/2009 |
| Q: The passengers in a roller coaster car feel 40% heavier than their true weight as the car goes ... A: Because this roller coaster is moving in a circular path Newton's 2nd Law applies: SF=m*a where SF ... | |
| Tension and angular velocity | 11/5/2009 |
| Q: A conical pendulum is formed by attaching a 420 g ball to a 1.0 m long string, then allowing the ... A: Because the mass of this pendulum is moving in a circular path it is accelerating and therefore its ... | |
| Pulleys | 11/5/2009 |
| Q: This is a question I have often wondered as I do a lot of sailing. When sailing we use block and ... A: In principle it is only the number of pulleys that matters. However, that completely ignores the ... | |
| Momentum | 11/4/2009 |
| Q: If two particles have equal kinetic energies, are their momenta necessarily equal? Sir Please ... A: Not at all! Kinetic energy is given by: KE=1/2*m*v^2 while momentum is given by: p=m*v Suppose that ... | |
| physics | 11/2/2009 |
| Q: A figure skater during her finale can increase her rotation rate from an initial rate of 1.0 rev ... A: This is a problem of angular momentum conservation where: I1*w1=I2*w2 where I is the moment of ... | |
| physics | 11/2/2009 |
| Q: A 6.0 m diameter merry-go-round is rotating freely with an angular velocity of 0.80 rad/s. Its total ... A: In an isolated system angular momentum will be conserved: I1*w1=I2*w2 where I is the moment of ... | |
| Optics | 11/1/2009 |
| Q: Respected Sir I am Mukul Of grade 12 Why does the wavelength of light change but the frequency ... A: When two mediums meet they form an interface. When a wave traveling in one medium encounters a ... | |
| theory | 11/1/2009 |
| Q: I just finished reading about Multiverse theory (altervative universes) and I don't understand if a ... A: Many experimental physicists would agree with your analysis. There doesn't seem to be any way, at ... | |
| emf of a solenoid | 10/31/2009 |
| Q: Imagine that you want to wind a solenoid that would be able to keep a 10-ohm light bulb lighted for ... A: The EMF generated by a changing magnetic flux is given according to Faraday's Law: EMF=-N*dF/dt ... | |
| physics | 10/31/2009 |
| Q: A 2.4 kg block slides down a 25° inclined plane with constant acceleration. The block starts from ... A: This is a straightforward kinematics problem with 6 unknowns and 2 equations. Any time you can ... | |
| physics | 10/30/2009 |
| Q: upper layers of water in a deep well are cool but those in a pond are warm and the lower layers of ... A: First of all, the assumptions made in this question are not universal. As for the well, if it is ... | |
| Physics | 10/29/2009 |
| Q: Sir, I want to know the procedure of how I can convert a Galvanometer into volmeter. A: To convert a Galvanometer into a Voltmeter you will have to place an appropriately valued resistor ... | |
| physics | 10/28/2009 |
| Q: A mallet consists of a uniform cylindrical head of mass 3.00 kg and a diameter 0.0800 m mounted on a ... A: What you are looking for here is the center of mass of the mallet. To find the center of mass let's ... | |
| can you please help me?? physics is my main struggle! | 10/28/2009 |
| Q: 1.Identify a sport and changing weather conditions that probably would cause an athlete to want to ... A: 1. Soccer? Think about it. It is not that hard. 2. Skiing? Try looking it up online [or maybe look ... | |
| Mouse trap car | 10/27/2009 |
| Q: I have to build a mouse trap car for physics. I've seen simple structures on the internet, but I ... A: Making the car go faster isn't the answer! Since the energy contained within the mouse trap is ... | |
| Physics:Conservation of energy | 10/26/2009 |
| Q: 1) AN older 925kg car without anti-lock brakes shows skid marks 15.3m long on wet pavement. the skid ... A: 1. Assuming that the coefficient of sliding friction between the tires of the car and a wet road is ... | |
| How does sound travel | 10/26/2009 |
| Q: My question is how does sound travel through the air? Is it like a radio wave? And is sound inside a ... A: Sound and light are entirely different. Light can travel through a vacuum while sound REQUIRES a ... | |
| Tension | 10/23/2009 |
| Q: A 20 kg loudspeaker is suspended 1.4 m below the ceiling by two 3.0 m long cables that angle outward ... A: This system is clearly at equilibrium since it is not accelerating. Therefore, opposite forces must ... | |
| physics | 10/22/2009 |
| Q: The blades in a blender rotate at a rate of 7000 rpm. When the motor is turned off during operation, ... A: The key to solving a rotational problem like this is just to pretend that the problem is linear! In ... | |
| physics | 10/22/2009 |
| Q: A grinding wheel 0.54 m in diameter rotates at 2300 rpm. (a) Calculate its angular velocity in ... A: To answer the first question use dimensional analysis [also called unit cancellation]: w=2300 ... | |
| physics | 10/21/2009 |
| Q: A spring (80 ) has an equilibrium length of 1.00 . The spring is compressed to a length of 0.50 ... A: All of these problems can be solved using the idea of energy conservation. 1. In this first problem ... | |
| physics | 10/20/2009 |
| Q: A skier coasts down a very smooth, 10-m-high slope. If the speed of the skier on the top of the ... A: These problems are all energy conservation problems! #1. The kinetic energy and gravitational energy ... | |
| physics | 10/20/2009 |
| Q: 1.) A ditch 2.5 m wide crosses a trail bike path. An upward incline of 15o has been built up on the ... A: If you looked at the previous 2 question I answered you would see: "Almost all two dimensional ... | |
| Physics motion | 10/19/2009 |
| Q: Divers in Acapulco dive from a cliff that is 64 m high. If the rocks below the cliff extend ... A: Almost all two dimensional kinematics can be done in the same way! Uniform acceleration involves six ... | |
| Physics motion | 10/19/2009 |
| Q: An airplane traveling 1010 m above the ocean at 120 km/h is going to drop a box of supplies to ... A: This is very much like the last question you asked! "Almost all two dimensional kinematics can be ... | |
| physics | 10/18/2009 |
| Q: Explain the difference between the everyday use of each term below and the way it is used in ... A: A) In everyday vernacular the word "acceleration" has come to mean "speed up". In physics, however, ... | |
| First year University Physics | 10/17/2009 |
| Q: Mr. Kovalcin, I'm doing review for a test I have soon and one of the questions I have is pretty ... A: Unfortunately you are on the wrong path! Your attempted solution implies that energy will be ... | |
| Physics - Calorimetry Lab | 10/16/2009 |
| Q: Mr. Kovalcin, I have a Physics lab in a little while and one of the introduction questions asks what ... A: Your answer seems to be on the right track. The point of the calorimeter is that in an isolated ... | |
| Torque and Rotational Dynamics | 10/16/2009 |
| Q: A 1.8 kg, 40 cm diameter disk is spinning at 340 rpm. How much friction force must the brake apply ... A: There are two different ways to approach this problem: energy conservation or kinematics. In either ... | |
| Sliding-Rolling Friction | 10/15/2009 |
| Q: If a ball is exhibiting non-pure rolling motion (i.e. sliding and spinning at the same time) in a ... A: Suppose that you have a bowling ball spinning clockwise when you gently release in onto a horizontal ... | |
| Physics | 10/13/2009 |
| Q: Starting from rest, a 92-kg firefighter slides down a fire pole. The average frictional force ... A: This problem is a combination of Newton's 2nd Law problem and a kinematics problem. First applying ... | |
| Physics | 10/12/2009 |
| Q: Kovalcin, I have a question that I am having a hard time figuring out. ---- An elevator whose mass ... A: In general there are only two equations needed to solve almost any one dimensional kinematics ... | |
| Physics | 10/11/2009 |
| Q: Kovalcin, I have a question that I am having a hard time figuring out. ---- An elevator whose mass ... A: Your are correct in that Power = Force x Velocity, but your answer is much too low! You must have ... | |
| PHYSICS | 10/11/2009 |
| Q: A HORIZONTAL FORCE=35NIS REQUIRED TO SLIDE A SWORD WEIGHING280KGF OVER A FLAT SURFACE CALCULATE ... A: Since the coefficient of friction mu is equal to the ratio if the force needed to overcome that ... | |
| AP Physics | 10/10/2009 |
| Q: two forces are applied to a car in an effort to move it. f1=450N@10degrees f2=400N@30degrees. ... A: The most reliable way to add two vector quantities is to use the i & j component method. In this ... | |
| Physics Question | 10/9/2009 |
| Q: A dockworker loading crates on a ship finds that a 20 kg crate, initially at rest on a horizontal ... A: The coefficient of friction is defined to be the ratio of the frictional force to the normal force ... | |
| velocity and gravity | 10/9/2009 |
| Q: My son is in freshman physics in high school. I didn't take physics "way back" when I was in ... A: The easy way to look at this is to use energy conservation! Since the ball is thrown with the same ... | |
| Earth's poles | 10/8/2009 |
| Q: I read in a magazine that the Earth's Magnetic poles "swtiches" polarities and have done so several ... A: As far as we know the Earth's magnetic field is caused by the fact that the Earth has an Iron-Nickel ... | |
| circular motion | 10/8/2009 |
| Q: The centers of a 9.0 lead ball and a 60 lead ball are separated by 11 . What gravitational force ... A: Assume that the m1=21kg sphere is at the origin, the m2=12 kg sphere is on the x axis at L=19.0cm ... | |
| heat flow through skin | 10/6/2009 |
| Q: I saw your answer to the problem of how much heat flows through the skin of a human with ... A: This is assuming that you have no hair covering, no clothes, minimal fat coverage, no surrounding ... | |
| Physics | 10/6/2009 |
| Q: A Cessna 150 aircraft has a lift-off speed of approximately 125 km/h What minimum constant ... A: All kinematics problems involve 6 variables [do, df, Vo, Vf, a and t] and two equations: ... | |
| conservation of energy | 10/5/2009 |
| Q: This may or may not be your type of question, but I don't know any other field to submit it to. ... A: The amount of energy needed to evaporate the water content of the clothes is the same in either ... | |
| Phsyics | 10/4/2009 |
| Q: In the high jump, the kinetic energy of an athlete is transformed into gravitational potential ... A: As in the previous question energy must be conserved. In this case the initial kinetic energy must ... | |
| Phsyics | 10/4/2009 |
| Q: Suppose the roller coaster in Fig. 6-41 (h1 = 34 m, h2 = 13 m, h3 = 20) passes point 1 with a speed ... A: Assuming that this roller coaster is heading downhill [since there is no diagram] the total kinetic ... | |
| Block and ramp variables | 10/3/2009 |
| Q: A spring pushes a block up a ramp with a frictional surface. How high can the block go before it ... A: The total energy stored in the system at the beginning must all be accounted for so that the total ... | |
| Physics | 10/2/2009 |
| Q: 3.) A 40kg mass is held on an inclined plane of 30 degrees above the horizontal. If the surface is ... A: If there is no friction, the force needed to hold the 40 kg mass in place will be the gravitational ... | |
| physics | 10/1/2009 |
| Q: Suppose the rope is 50 meters long, and that a sideways force of 300 N is required to displace the ... A: Since force is a vector quantity the force components must be directly proportional to the distances ... | |
| please help | 9/30/2009 |
| Q: ,i was wondering if u could help me with this, i need the general equation of motion. a robot is ... A: Assuming that the wall is vertical, the downward gravitational force Fg on the robot needs to be ... | |
| rate of acceleration | 9/29/2009 |
| Q: Question on rate of acceration concerning an combustion engine. displacement of 10 cm Piston moves ... A: Assuming that this piston's motion is simple harmonic: a=A*w^2 The maximum acceleration a will be ... | |
| physics stumper i need help | 9/28/2009 |
| Q: Two billiard balls having the same mass and speed roll toward each other. What is their combined ... A: Their combined momentum after will be exactly the same as their combined momentum before [if you ... | |
| physics | 9/24/2009 |
| Q: A commuter train was traveling into the train station. It failed to stop on time and crashed into ... A: The passengers would NOT fly backwards! Remember that the train is moving forward and so are the ... | |
| physics | 9/23/2009 |
| Q: my question is: If two snowcats tow a housing unit to a new location, the sum of the forces FA and ... A: The components of the two forces perpendicular to L must be equal: Fa*sin(50)=Fb*sin(30) solve for ... | |
| physics | 9/23/2009 |
| Q: what's the connection between speed, friction, and radius of the curve when turning? A: Assuming that the curve is flat [that is, the road bed is horizontal]. The force needed keep ... | |
| Physics | 9/22/2009 |
| Q: A ball is dropped into a lake 5 meters above water. It enters the water and sinks to the bottom with ... A: Aside from the fact that this would never happen! First calculate the velocity of the ball after it ... | |
| Pumping with Compressed Air | 9/21/2009 |
| Q: James, I am trying to work out why an air displacement pump delivering to a 50 metre head through 2 ... A: Several things! First, the inertia of the water down not matter unless you are accelerating the ... | |
| General Physics | 9/21/2009 |
| Q: Respected sir I am a student of grade 12 Capacitive reactance is inversely proportional to the ... A: As charge flows onto the plates of a capacitor the potential difference across the capacitor builds ... | |
| Electromagnetics | 9/20/2009 |
| Q: Respected Sir I am student of class 12, Is there any condition or an example in which emf is induced ... A: Sure! Just because an EMF exists no way implies that a current exists. Current will only flow if it ... | |
| Questions related to diodes, relativity and radiation | 9/19/2009 |
| Q: Given below are some questions which I have attempted and all I want to know now is whether they are ... A: 8. The red light will have to have more photons since each photon of red contains less energy. E=h*f ... | |
| Relative Motion Problem | 9/19/2009 |
| Q: The bad guys come roaring onto a highway at 150 km/h headed for the Mexican border 395 km away. The ... A: This is a kinematics question with two objects and, therefore, two data sets. The key to the problem ... | |
| Projectile Motion | 9/18/2009 |
| Q: In a flat region, a projectile is fired in such a way that it's horizontal range is equal to three ... A: To solve a 2 dimensional projectile problem you need to break the problem into two parts; one ... | |
| physics | 9/18/2009 |
| Q: A skier is gliding along at 4.5 m/s on horizontal, frictionless snow. He suddenly starts down a 10° ... A: There are actually two distinctly different ways to solve this problem: through kinematics and ... | |
| Physics-experiment | 9/17/2009 |
| Q: Describes the steps you would take in an idealized experiment to determine the unknown mass (m) of a ... A: I don't want to give you all the answers - you will have to fill in the blanks. The general idea ... | |
| physics | 9/15/2009 |
| Q: The potential difference between the plates of a capacitor is 185 V. Midway between the plates, a ... A: Tough problem! Realize that both the electron and the proton are going to fall through the same ... | |
| physics | 9/14/2009 |
| Q: A 4kg block stretches a spring by 16cm form its unstretched position the block is removed and a 5kg ... A: According to Hooke's Law the amount a spring stretches is proportional to the magnitude of the force ... | |
| quantum | 9/12/2009 |
| Q: First I want to apologize for the length of this question bu I'm confused! I'm reading a book, it ... A: If I could answer that question I would be up for a Nobel Prize! I am not kidding. All work done in ... | |
| multimeter | 9/12/2009 |
| Q: I bought a multimeter that measures either voltage or current. I have never seen this. I have only ... A: My first concern when you talk about household wiring is that you MUST not do anything until you ... | |
| Pumping with Compressed Air | 9/11/2009 |
| Q: James, I am trying to work out why an air displacement pump delivering to a 50 metre head through 2 ... A: I did the calculation and got that you need 55psi to lift the water to 40 meters. ... | |
| quantum | 9/10/2009 |
| Q: First I want to apologize for the length of this question bu I'm confused! I'm reading a book, it ... A: You are correct: it would be more correct to say that there is an equal probability that the ... | |
| physics | 9/10/2009 |
| Q: what voltage is required to store 6.45x10^-5 C of charge on the plates of a 5.60-uF capacitor? A: The capacitance of a capacitor is defined to be equal to the ratio of the charge stored on the ... | |
| physics | 9/8/2009 |
| Q: Could you help me how to give a mathematical explanation on the basis of the Conservation of Angular ... A: If you multiply the moment of inertia of a rotating object by its angular velocity the resulting ... | |
| dualityof light | 9/8/2009 |
| Q: why cant light behave like a wave and a particle atthe same time? A: That is not really the point. It is not that light CAN'T behave as a wave and as a particle at the ... | |
| Electricity | 9/2/2009 |
| Q: Is neutral wire becoming hot,during the positive alternation?or is hot wire return path in this ... A: The fact that current reverses direction in an AC circuit does not matter. Current going either way ... | |
| velocity/ acceleration | 9/2/2009 |
| Q: A stone is dropped from the top of a building 20m hight. A second stone is dropped from 15m of the ... A: To answer this question you need to find the time for each stone to drop to the ground and then ... | |
| atoms | 9/1/2009 |
| Q: I was wondering, if atoms have electromagnetic energy does this mean that they all have ... A: When one says that atoms have "electromagnetic energy" what is really meant is that the system ... | |
| windmills | 8/31/2009 |
| Q: I am trying to make a windmill. Please look at my sketch. Can you think of an answer to my two ... A: You would need something that permitted air to pass one direction but not the opposite. If you go to ... | |
| archimedes principle and principle of floatation | 8/29/2009 |
| Q: how can i differentiate between Archemedes principle and principle of floatation? why the buoyant ... A: Both situations make use of Newton's 1st Law! For a floating object the gravitational force downward ... | |
| physics | 8/26/2009 |
| Q: How can I design an experiment to measure the center of gravity of doughnut, if I know its center is ... A: To find the center of mass suspend the donut from any pivot point with a weighted string hanging ... | |
| atoms | 8/26/2009 |
| Q: I hope this isn't a question that will prove too general or complicated to answer to a person who ... A: The atom, i a sense, doesn't look like much. Effectively the nucleus is surrounded by very rapidly ... | |
| microwave damage to water | 8/25/2009 |
| Q: <my health food friends tell me that you should not eat microwave food because it destroys all of ... A: Sorry, but it is just nonsense! Any damage to the nutrients in the food will be due to the fact that ... | |
| time | 8/25/2009 |
| Q: I saw a special on the science channel that indicated that it was possible to go back in time either ... A: Since all fundamental particles of a particular type are indistinguishable from one another [all ... | |
| Quantum physics | 8/24/2009 |
| Q: My Question is this:- When matter is created as I understand it, its anti particle is also created ... A: When energy is used to generate particles, the resulting particles occur in pairs. The vast majority ... | |
| time | 8/24/2009 |
| Q: I saw a special on the science channel that indicated that it was possible to go back in time either ... A: There are many things to comment on here! First of all, don't confuse speculation with reality. ... | |
| gravity? kenetic energy? | 8/20/2009 |
| Q: Playing the piano (keyboard): A fast arpeggio on keyboard, high notes to low ( e.g. with right ... A: I can only surmise that there must be a component of the gravitational force acting in the direction ... | |
| Angular momentum & Earth's axial tilt. | 8/20/2009 |
| Q: I'm having trouble establishing the veracity of the claim that the moon somehow stabilizes the angle ... A: I think the best answer to this question can be illustrated from a high wire act where the person ... | |
| Buoyancy | 8/19/2009 |
| Q: I'm trying to understand the relative effect of buoyancy, volume, and depth. If I tied a balloon ... A: Your first statement is correct assuming that the balloon is completely submerged and that the ... | |
| thermal Physics | 8/18/2009 |
| Q: I have spent time trying to understand and answer the following question. Would you be so kind to ... A: Given a solar insolation of 342W/m^2 and an area of 50 m^2 this lake is receiving: ... | |
| Newton's Cradle | 8/18/2009 |
| Q: James, thanks for taking the time to read my question. I'm not a student, just fascinated in the ... A: Theoretically it should not matter, but in practice the difference would be significant. The problem ... | |
| physics | 8/17/2009 |
| Q: sir can you please tell me what is gravitational acceleration all about A: The gravitational effect of mass is to warp the shape of space in the vicinity of the mass causing ... | |
| Breaking light speed | 8/14/2009 |
| Q: James, thanks for taking the time to read my question. I'm not a student, just fascinated in the ... A: You cam come up with ant situation you can imagine but that will not change the fact that NO ONE has ... | |
| Galvanometer to Voltmeter | 8/13/2009 |
| Q: for the experiment of using a galvanometer as a voltmeter what kind of graphs can i make? and what ... A: To make a galvanometer into a voltmeter you need to connect a relatively high ersistane in series ... | |
| transverse waves | 8/11/2009 |
| Q: in transverse waves is the speed of a particle different from speed of the wave propagation, or how ... A: The speed of a wave through a medium [the propagation velocity] and the speed of the particles are ... | |
| optics | 8/9/2009 |
| Q: what is the difference between a convex lens and concave lens? A: A convex lens will be thicker at the center than at the edges and it will be able to form and ... | |
| impact of an object on a 3/4" of plywood | 8/8/2009 |
| Q: Given an object falling from a height of 190' (57.912 m) with a weight of 10 pounds (4.54kg) what ... A: The kinetic energy KE of the falling mass as it reaches the plywood will be equal to the ... | |
| restitution | 8/6/2009 |
| Q: how can we calculate height of a ball it it bounces two or three times A: Two factors need to be taken into account here: energy conservation and coefficient of restitution. ... | |
| electrostatics | 8/2/2009 |
| Q: what do you mean by electric potential of a rod is 5v? what is potential difference? A: Potential difference is a measure of how much work must be done per unit charge to move that charge ... | |
| ..please help me and my group.. | 8/1/2009 |
| Q: ..hello i just wanted to ask if you have some idea for a fourth year high school investigatory ... A: There are many projects that you could do! Let me list a few! 1. Build a "Rube Goldberg" machine. ... | |
| MECHANICS | 8/1/2009 |
| Q: A UNIFORM ROD,AB OF LENGTH 4a IS ELEVATED AT THE 'A' END. THE 'B' END IS 30DEGREES TO THE ... A: I am making the assumption that point A is on the left and is the center of rotation of the system. ... | |
| engineering and technology | 7/31/2009 |
| Q: What is meant by engineering and technology? A: From a practical point of view "Engineering & Technology" refers to the carefully planned use of ... | |
| physics | 7/26/2009 |
| Q: Two pellets, each with a charge of 1microcoulomb are located 3cm apart. Show that the electric force ... A: The electrostatic force between two charged bodies is given by: Fe=k*q1*q2/r^2 where k=9.0 x 10^9 ... | |
| Law of Conservation of Momentum | 7/25/2009 |
| Q: Today we had a practical lesson involving two gliders moving on an airtrack. The first glider was ... A: Depending upon how you measured the velocities, there is a lot of error in the typical apparatus ... | |
| Law of Conservation of Momentum | 7/24/2009 |
| Q: Today we had a practical lesson involving two gliders moving on an airtrack. The first glider was ... A: The fact is that this experiment is relatively difficult to perform successfully because of friction ... | |
| physics | 7/24/2009 |
| Q: what is the energy of an electron accelerated through a potential difference of 100 volts A: Accelerating an electron through a potential difference of 100 volts produces an energy of 100 ... | |
| theory of relavity | 7/23/2009 |
| Q: This qustion is regarding relativity of time. suppose i have 2 bodies: A and B. Body A is earth.? ... A: Sorry, there is no way to determine the mass of object B based on the given information. However, ... | |
| Physics | 7/22/2009 |
| Q: Where should the birthday candle of height 5 cm be placed in front of a convex lens of focal length ... A: The position of the object do, the position of the image di and the focal length of a mirror or lens ... | |
| Gravity and the Coriolis effect | 7/20/2009 |
| Q: I was wondering if gravity could be created by spinning a ring around a large diameter round ... A: Spinning space stations do not really create "gravity"! What they actually do is to generate an ... | |
| inclined plane friction | 7/19/2009 |
| Q: I am doing an EEI. My experiment was to roll golf balls down an inclined plane in order to test ... A: This problem is, fundamentally, a Newton's 2nd Law problem. As such, the first step is to make a ... | |
| Derivation Bimettalic Strip | 7/19/2009 |
| Q: How did Dr. Lewin derive the value d= 4 mm in the video: http://www.youtube.com/watch?v=sr0yMWdWie0 ... A: Assume that the bimetallic strip curves into a uniform circular section subtending and angle Q. The ... | |
| Einstein's photoelectric equation | 7/17/2009 |
| Q: Explain why the graph of photoelectric effect experiment always has the same gradient whatever metal ... A: According to the photo-electric equation the kinetic energy of the released electrons is given by: ... | |
| physics | 6/23/2009 |
| Q: Starting from rest, a ball of mass 2 kg experiences a constant force of 2 N. What is the final ... A: One way top solve this problem would be! 1. Use Newton's 2nd Law to solve for the acceleration: ... | |
| Prism | 6/23/2009 |
| Q: Could you please tell me what is the name of the starting point from where beam is converted into ... A: A beam of light isn't "converted" into different colors, rather, the prism takes the various colors ... | |
| Electricity | 6/20/2009 |
| Q: Is neutral wire becoming hot,during the positive alternation?or is hot wire return path in this ... A: That is not really the issue. Current always flow in the neutral wire. What is special about the ... | |
| Physics | 6/19/2009 |
| Q: An electric furnace runs nine hours a day to heat a house during January (31 days). The heating ... A: A kilowatt hour is a measure of energy and is equal to the product of the rate of energy use in ... | |
| physics | 6/19/2009 |
| Q: Block 1 (2 kg) rests on the surface of a table as shown in the figure. The coefficient of kinetic ... A: The block weighs Fw=2*9.8=19.6N. Since the coefficient of friction is 0.5, the frictional force will ... | |
| physcs | 6/18/2009 |
| Q: Block 1 (m1 = 1.5 kg) is on the surface of a table as shown in the figure. The rope attached to the ... A: First break the applied force Fa into horizontal and vertical components. I this case the components ... | |
| physics | 6/17/2009 |
| Q: The force F = (80, 40) N acts on a mass of 10 kg. At time t = 0 s, the mass has a velocity v0 = ... A: 1) To find the direction of the initial velocity calculate the direction using the tangent function: ... | |
| Physics | 6/16/2009 |
| Q: A woman finds the front windshield of her car covered with ice at -12.0°C. The ice has a thickness ... A: The heat of fusion for ice is 334 joules per gram while the specific heat of ice is 1.87 joules per ... | |
| Physics | 6/15/2009 |
| Q: A person who is 1.5 m tall throws a ball with a speed of 9.8 m/s at an angle of 70 degrees above the ... A: All two dimensional kinematics problems can be solved in the same way! There are 6 possible ... | |
| Projectile Movement | 6/14/2009 |
| Q: A stone is thrown downward with a speed of 1 m/s from a height of 14 m. (acceleration due to ... A: All one dimensional kinematics problems can be solved in the same way! There are 6 possible ... | |
| Electricity-Capacitance | 6/13/2009 |
| Q: Explain why it is that some items of electronic equipment have the warning message 'Danger: Even ... A: Unless the capacitors within the electronic device have been purposely discharged, they can store ... | |
| Electrical Fields/Electric Charges | 6/13/2009 |
| Q: Given:There is an atom with a charge of +1 micro coulomb placed 1 centimeter from an atom with a ... A: First of all, these CANNOT be atoms! A 1 microCoulomb charge contains ... | |
| Physics Problem | 6/12/2009 |
| Q: A 1200 kg racing car accelerates from rest at a constant rate and covers a distance of 450 m in 10 ... A: All one dimensional kinematics problems can be solved in the same way! First identify as many of the ... | |
| inductance | 6/11/2009 |
| Q: Could you explain the following sentance. The inductance can be minimized by winding the insulated ... A: The inductance of a coil is determined by the rate of change of magnetic flux within the coil. When ... | |
| gravity vs. drag | 6/10/2009 |
| Q: If you drop two balls of I dentical size and shape, but A is made of wood (light) and one is made of ... A: Newton's 2nd Law: SF=m*a where SF is the sum of the forces, m is the mass and a is the acceleration. ... | |
| atomic | 6/10/2009 |
| Q: Are the electron neutron and proton breakable ? what remains if any of them is broken ? A: Protons and neutrons are composite particles! Each particle contains 3 quarks. Each proton is made ... | |
| gravity vs. drag | 6/9/2009 |
| Q: If you drop two balls of I dentical size and shape, but A is made of wood (light) and one is made of ... A: No! The rate of acceleration of each ball is determined by the NET force acting on the ball. Since ... | |
| Physics | 6/5/2009 |
| Q: Light reflected from the surface of a liquid is found to be completely polarised when the angle of ... A: 1. According to Brewster's Law, maximum polarization occurs when the tangent angle of incidence is ... | |
| how does a convex mirror work? | 6/4/2009 |
| Q: when a convex mirror is installed to be a security mirror or such, i know that they're better than ... A: A convex mirror works by redirecting light that strikes it such that light coming from a wide ... | |
| Law of Conservation of Energy | 6/3/2009 |
| Q: We did an experiment in class today involving rolling a ball down a slope. I calculated the change ... A: The ball didn't gain any extra energy. It is just that the initial gravitational energy will be ... | |
| Wheatstone Bridges | 6/2/2009 |
| Q: How do Wheaststone Bridges work, and how can they be used to calculate the resistance of unknown ... A: In a Wheatstone Bridge circuit, the resistor in the bridge is replaces by a galvanometer. Why, you ... | |
| alpha | 6/1/2009 |
| Q: Alpha particles perpendicular undeflected through magnetic and electric fields that are ... A: If the alpha particle moves through crossed electric and magnetic fields and passes through the ... | |
| About electric field | 5/31/2009 |
| Q: What are the differences between electric and magnetic fields? thanks a lot A: They are VERY different. An electric field E is an area of space where any particle with a charge q ... | |
| a falling object | 5/30/2009 |
| Q: James well when an object is falling vertically downward having 'g' as an acceleration, and then ... A: When you lift an object upward you have to do work on it. This work increases the gravitational ... | |
| radius of an arc | 5/29/2009 |
| Q: X^+2 and Y^+ ions, whoes masses are 8.35 x 10^-27 kg and 3.34 x 10^-27 kg respectively, traveling at ... A: For a particle moving in a circular path in a uniform magnetic field Newton's 2nd Law predicts: ... | |
| Ionization | 5/29/2009 |
| Q: if a hydrogen atom is in level 2 and is hit by a 332 nm photon how do you show that the electron ... A: Solve this problem by using energy conservation! The energy of the incoming photon of light E=h*c/l ... | |
| a question of time dilation in special relativity from a (currently) layperson's perspective | 5/28/2009 |
| Q: On a purely logical level, ideally with only any basic math that may be necessary, not having ... A: The problem here, is that both the observer on the Earth and the observer on board the rocket will ... | |
| throw | 5/27/2009 |
| Q: When rain (with constant velocity), if you want walk from one place to another place how can you go ... A: This is an answer that I just did yesterday! I propose breaking this up into two parts: one ... | |
| Running in the Rain? | 5/26/2009 |
| Q: When rain (with constant velocity), if you want walk from one place to another place how can you go ... A: I propose breaking this up into two parts: one horizontal and one vertical. I made the following ... | |
| Millikan | 5/24/2009 |
| Q: In 1912, Robert Millikan noticed that charged plates would clear condensed water vapour (fog) from a ... A: This problem is essentially a Newton's 1st Law problem, the electrostatic force upward caused by the ... | |
| Millikans oil drop | 5/24/2009 |
| Q: A student performs Millikan oil drop experiment in which latex sphere with a mass of 5.00 x 10 to ... A: This problem is essentially a Newton's 1st Law problem, the electrostatic force upward caused by the ... | |
| radius | 5/22/2009 |
| Q: A proton enters a magnetic field at a right angle to the field. An alpha particle enters the same ... A: For a charged particle moving perpendicularly to the magnetic field the resulting magnetic force ... | |
| Physics | 5/21/2009 |
| Q: I just got this questions and I don't even know how to start it It will be awesome and really ... A: Use energy and momentum conservation! The initial kinetic and gravitational energy of the S10 pickup ... | |
| Balmer Series | 5/21/2009 |
| Q: The regions of the electromagnetic spectrum into which the lines of Balmer Series of hydrogen are ... A: The Balmer spectrum of Hydrogen corresponds to electrons moving from n=3,4,5 and 6 down to level n=2 ... | |
| How a PN-junction diode works? | 5/18/2009 |
| Q: It would be most helpful if you could explain to me how a PN junction diode really works. I already ... A: The key to this question is the degree of doping done to the semiconductors. Actually, the number of ... | |
| minimum angular velocity | 5/17/2009 |
| Q: if a 6 sided mirror and a fixed mirror are 45.0km apart. What minimum angular velocity in (RPS) that ... A: If the fixed mirror is 45km away, the round trip for lint would be 90km. Since the speed of light is ... | |
| question about anti-matter and the movies | 5/17/2009 |
| Q: In the new Tom Hanks movie they "created" anti-matter into glass vials, suspended between two ... A: First of all, antimatter is NOT negative. Most antimatter just has a charge opposite that of the ... | |
| movement | 5/15/2009 |
| Q: A motor car is 500kg and it accelerates from a velocity of 18m/s to 50m/s in 5 seconds. How do I ... A: All problems of this type can be solved in the same way. There are six kinematics variables and two ... | |
| mass of balloon | 5/14/2009 |
| Q: What is the average mass of a standard water balloon? A: I don't think that there is a "standard" water balloon. However, water weighs about 8 pounds per ... | |
| Terminal velocity | 5/14/2009 |
| Q: I have a student who argues that the impact from a person falling from a three story building would ... A: The force acting on the falling person when they strike the ground would be given by Newton's 2nd ... | |
| Inductance of wire | 5/13/2009 |
| Q: I believe for a straight piece of wire the inductance is roughly 1nH a millimetre (I guess it ... A: I think that you will find the information you require regarding a long straight wire at ... | |
| Newton's 3rd Law | 5/13/2009 |
| Q: Say a mosquito hits a bullet train. The law states that for every action there is an equal and ... A: Just because the force on the mosquito is equal to the force on the train does NOT mean that the ... | |
| When do two objects officially touch? | 5/12/2009 |
| Q: This was probably asked a million times before, but I'd like to know the following: When is ... A: This question is virtually impossible to answer. But there are limits to how small of a length we ... | |
| Motion and conservation of energy | 5/12/2009 |
| Q: Mr. Kovalcin, This is the data for a roller coaster. Instead of a cart though, it is a ball of mass ... A: In the first case energy seems to be conserved within experimental error in all cases. In the second ... | |
| Maximum frequency | 5/11/2009 |
| Q: cathode rays strike a metal target travelling at 8.50 x 10^6 m/s. what is the maximum frequency of ... A: This is called the "inverse photoelectric effect". The kinetic energy of the incoming electrons ... | |
| Musical Acoustics | 5/11/2009 |
| Q: If the velocity of transverse waves on a certain string of length L=0.3 m is v(subscript t)=240 m/s, ... A: If a string is attached at each end, the smallest part of a standing wave that can resonate on that ... | |
| Photons | 5/10/2009 |
| Q: The power in a laser beam is equal to the energy of each photon times the number of photons per ... A: The energy of a light wave is given by: U=h*f=h*c/L where U is the the energy content of the wave, f ... | |
| voltage, electron | 5/10/2009 |
| Q: An electron is accelerated from rest through a potential difference. If this electron has a ... A: According to the deBroglie relationship: h/L=p where h is Planck's constant, L is the wavelength ... | |
| radius | 5/9/2009 |
| Q: Given the wavelenght of an electron 2.08 x 10^-9 m, calculate the radius of the deflection arc that ... A: If you know the wavelength of the electron, you can determine the speed of the electron using the ... | |
| Einstein Nobel Prize | 5/7/2009 |
| Q: I know Albert Einstein received the Nobel Prize for his work on the photoelectric effect. Why did he ... A: The tradition of the Nobel Prize is that a person can only receive the prize once in a particular ... | |
| Electromagnetic theory | 5/5/2009 |
| Q: Two parallel rails are connected together at one end by a resistanceof R = 20.0 W as shown in the ... A: According to Faraday's Law the EMF generated in the closed conducting path is given by: EMF=-Df/Dt ... | |
| mass | 5/4/2009 |
| Q: i wanna ask how we can calculate mass of objects in space which no gravity exists!!? would u please ... A: One way to do this is to use an "inertial" balance, which consists of a container vibrating on the ... | |
| release velocity | 5/2/2009 |
| Q: This is a question from my uil calculator contest. I could not figure out the steps to the ... A: This is a typical 2 dimensional kinematics problem. There are 6 possible variables: Do - the initial ... | |
| physics | 5/1/2009 |
| Q: i am not extremely that good in physics so i deemed it useful to keep practicing. i came across a ... A: Making the following assumptions! Distance to water from bridge - h Length of unstretched bungee ... | |
| natural frequency | 5/1/2009 |
| Q: How does the sound of a string vibrating at its natural frequency compare to its sound at other ... A: A string vibrating at a particular fundamental frequency will also resonate at any integer multiple ... | |
| WAVE-PARTICLE DUALITY | 4/30/2009 |
| Q: Q:The DeBroglie wavelength of a particle is given by lambda=h/mv. Two properties of the particle ... A: The group action explanation doesn't sound right to me. On the other hand, the wavelength of a ... | |
| tire speed | 4/30/2009 |
| Q: My friends and I were arguing the other day if the center of a car tire going 50 mph, the same as ... A: Actually, no! If the car is moving down the highway at 50mph, the top edge of the tire will be ... | |
| capacitance | 4/29/2009 |
| Q: I need help with the following: A parallel capacitor has a capacitance of 10mF and is charged with a ... A: The capacitance of a parallel plate capacitor is given by: C=eo*K*A/d where eo=8.85 x 10^-12 ... | |
| Physics | 4/29/2009 |
| Q: Does an electron always experience a force in an electric field but not always in a magnetic field? A: The electric force on a charged particle in an electric field is given by: Fe=E*q. The magnetic ... | |
| Light Bulb that never burns out | 4/27/2009 |
| Q: Looking at this webpage: http://www.newton.dep.anl.gov/askasci/gen99/gen99654.htm It seems to say ... A: An ordinary light bulb filament "burns out" not because of oxygen but because of the gradual ... | |
| energy | 4/24/2009 |
| Q: Your help is very much appreciated. 1- A novice skier, starting from rest, slides down a ... A: 1. Using energy conservation the skier begins with gravitational energy and ends with kinetic: ... | |
| Heat flow through skin | 4/23/2009 |
| Q: A person has a core (inner) body temperature of 36degrees C, and the air temperature is 20degrees ... A: That rate at which heat flows through a surface DQ/Dt is given by: DQ/Dt=sigma*A*DT/d where sigma ... | |
| Baseball hits a person in dugout? | 4/21/2009 |
| Q: If a person in the dugout is hit in the face or head area, by a foul ball (hard hit line drive), ... A: Of course! Here are the results of a recent 2007 study: "BASEBALL - HIGH SCHOOL A 14 year-old high ... | |
| Equation for baseball height and distance | 4/18/2009 |
| Q: A boy hits a baseball and it travels for 440 feet before it lands. When he hits the ball it is ... A: All 2 dimensional freefall problems can be solved in the same way! Because this is a two dimensional ... | |
| optics | 4/17/2009 |
| Q: why are convex mirrors used as driving mirrors? A: A convex mirror gives a greater range of view than a plane mirror. There is one problem, however. ... | |
| Speed of Light | 4/17/2009 |
| Q: If a car is traveling 20 miles per hour and turns on its headlights, will the light be traveling the ... A: I know this may not make much sense, but the speed of the light emitted by the moving car will be ... | |
| trouble with simple harmonic motion | 4/15/2009 |
| Q: I have this right or wrong question that i know the answer to but not the way to solve it can you ... A: You are assuming that the spring CONSTANT is changing! In general, the spring constant is determined ... | |
| Light bulb efficiency vs filament temperature | 4/14/2009 |
| Q: Could you tell me why a hotter filament is more efficient than a cooler one? (why you get more ... A: The rate at which light is radiated from a hot object is given by: DQ/DT=sigma*emissivity*A*T^4 ... | |
| Physics: Ideal Gases | 4/14/2009 |
| Q: Kovalcin, My lab TA suggested that we try to answer the following multiple step question as ... A: All of these questions use the ideal gas law: P*V=n*R*T 1. If you add heat to a gas the temperature ... | |
| trouble with simple harmonic motion | 4/13/2009 |
| Q: I have this right or wrong question that i know the answer to but not the way to solve it can you ... A: I think that you already have the answer! The period of a mass oscillating on the end of a spring is ... | |
| An ascending air bubble | 4/13/2009 |
| Q: An air bubble ascends from the bottom of a lake 12.3m deep. The temperature at the bottom of the ... A: To solve all problems of this type use the universal gas law: P*V=n*R*T where P is the absolute ... | |
| Magnitude | 4/12/2009 |
| Q: Two ropes are attached to a 40 kg object, which rests on a horizontal surface. The first rope ... A: The resultant of two forces acting perpendicularly to one another can be found using the Pythagorean ... | |
| Work Engery Theorem | 4/12/2009 |
| Q: Eric pulls a 15 kg box across a horizontal, frictionless floor by a rope starting from rest. The ... A: According to the Work-Energy Theorem, the change in the energy of a system is equal to the net work ... | |
| Physics-Light | 4/11/2009 |
| Q: When the outer electrons that buzz about the atomic nucleus encounter electromagnetic waves, what ... A: Several different results can occur! 1. If the incoming EM wave has too little energy [more about ... | |
| Hydrogen gas baloon | 4/11/2009 |
| Q: You place 87 moles of hydrogen gas in a balloon of volume 2.4m3, and find the pressure to be 1.5 ... A: 1. Use the Universal gas law to determine the temperature of the gas. 2. Use the temperature of the ... | |
| friction | 4/7/2009 |
| Q: A 182 g block is launched by compressing a spring of constant k=200 N/m a distance of 15 cm. The ... A: This problem is, of course, an energy conservation problem. Initially, all of the energy in this ... | |
| Potential energy | 4/6/2009 |
| Q: A 120g arrow is shot vertically from a bow whose effective spring constant is 400 N/m, if the bow is ... A: Use energy conservation! The elastic energy EPE at the beginning will be equal to the gravitational ... | |
| Urgent. need help!! | 4/4/2009 |
| Q: The electric field inside a hollow conductor is zero. I cant prove this statement. How can i prove ... A: There are two different ways to approach this! 1. According to Gauss' Law, the strength of the ... | |
| Kinetic energy of a mass-on-a-spring oscillator | 4/3/2009 |
| Q: The position of a mass-on-a-spring oscillator is given by y = A sin(23 t) where the value of t is ... A: For any simple harmonic oscillator the displacement from equilibrium is given by A=Ao*sin(w*t) ... | |
| physics/power | 4/2/2009 |
| Q: A given load is to be raised through a vertical distance of 10 meters in 30 seconds by using a force ... A: Power is defined to be the work done divided by the time over which the work is done. Since work is ... | |
| magnetism | 4/2/2009 |
| Q: A hollow copper cylender carrying current why B=0(magnetic density) inside? do u think that outside ... A: I suspect that my answer will still not be satisfactory and for good reason! Magnetism is, in ... | |
| magnetism | 4/1/2009 |
| Q: can you explain the answer to question 21 to me on this page ... A: According to Faraday's Law any change in the magnetic flux within a closed conducting path will ... | |
| magnetism | 4/1/2009 |
| Q: When two parallel conducting wires repel each other, the currents in the wires are A. in opposite ... A: Assume that the two wires are running vertically from the top of the page towards the bottom of the ... | |
| Waves | 3/31/2009 |
| Q: Sonar: Suppose you are fishing using your handy dandy new sonar. The sonar display tells you there ... A: Since the speed of sound is significantly faster in water [~1435m/s] than in air [~346m/s], the time ... | |
| Waves | 3/31/2009 |
| Q: If you are very far away from an object when it is hit, you often see the collision before you hear ... A: The speed of light in air is about 186,000 MILES per second, while the speed of sound in air is ... | |
| Screw Jack Calculation | 3/30/2009 |
| Q: I am 46 and have to figure this out. If a screw jack has a pitch of 3mm, a double start thread, a ... A: I think that this question is missing an important piece of information, the diameter or radius of ... | |
| magnetism | 3/30/2009 |
| Q: A hollow copper cylender carrying current why B=0(magnetic density) inside? do u think that outside ... A: The magnetic field within the hollow tube will be zero, but outside the tube the magnetic field ... | |
| calculating speed ( magnetic field) | 3/27/2009 |
| Q: The conducting rod in the diagram is 54 cm long, and is moved at a constant speed perpendicular to ... A: According to Faraday's Law the EMF [the increase in potential difference] generated by a changing ... | |
| electroscope | 3/26/2009 |
| Q: 27. A positively charged rod is held near the sphere of a neutral electroscope. a. What happens to ... A: When you move the positive rod near to the sphere at the top of the electroscope, the rod will ... | |
| Magnetics question on calculating energy gained | 3/24/2009 |
| Q: Can anyone help me with question 17 on this page http://www.studyphysics.ca/30/phys30_jan02_de.pdf ... A: Potential difference V is equal to work done per charge: V=W/q Therefore, the work done on a charged ... | |
| Magnetic field help | 3/23/2009 |
| Q: An electron particle is accelerated by a potential difference of 2.33 x 10^3 V as it travels ... A: When a charged particle is accelerated by a potential difference V, the energy U gained by the ... | |
| physics | 3/23/2009 |
| Q: Three blocks are pulled by a force of 16.5 newtons along a frictionless surface, the boxes are ... A: According to Newton's 2nd Law, the sum of the forces acting on a system is equal to the product of ... | |
| centripetal force | 3/22/2009 |
| Q: I have trouble to understand: the DEF of centripetal force? A: Consider a car moving forward at a constant speed. If you apply a force in the direction of the ... | |
| Magnetics | 3/21/2009 |
| Q: I having problems on questions 20 and 21 on this practice exam site: ... A: 20) Assume for a moment that you have two wires, parallel to one another and pointing into the page. ... | |
| Conservation of Linear Momentum ... Please Help!! | 3/21/2009 |
| Q: I really do need help with this question . I think my hardest part is identifying the different ... A: Let me start be defining some variables! m1=55kg mass of the girl m2=80kg mass of the boy m3=0.050kg ... | |
| electric force | 3/20/2009 |
| Q: Two charged objects of identical size and mass are brought together in brief contact. If the one ... A: When you touch the identical balls together, the charges on the two balls interact and neutralize ... | |
| Coefficient of friction | 3/20/2009 |
| Q: can you help. the question is, A child drags a 3kg(29.4N) boogie board across the sand by means of a ... A: Since the sled is being pulled at a constant speed, the system is at equilibrium and opposite forces ... | |
| gravitational and gravitational fiels | 3/19/2009 |
| Q: please PLEASE help me... a satellite is designed to orbit earth at an altitude above its surface ... A: Do you mean 4.5m/s^2? Your question as stated has no real answer. If you do mean a gravitational ... | |
| electric potential | 3/16/2009 |
| Q: A Coulomb explosion occurs when a high-energy complex ion is brought to rest in a collision with a ... A: The energy of the Helium ion is: E=3.0Mev=3.0x10^6eV*1.6*10^-19J/eV=4.8x10^(-13)J Potential ... | |
| Coulomb explosion | 3/15/2009 |
| Q: A Coulomb explosion occurs when a high-energy complex ion is brought to rest in a collision with a ... A: 1. Electrostatic potential difference is equal to work done per charge: V=W/q. The work done on the ... | |
| Wind | 3/15/2009 |
| Q: Modern Sail boats are able to "move" against the wind in a monouvere called tacking.This is only ... A: Because of the Earth's rotation the prevailing winds are id different direction depending on the ... | |
| mechanics problems | 3/14/2009 |
| Q: A box, initially at rest, is pulled up an incline by a force F = 50 N parallel to it. The incline ... A: First make a freebody diagram labeling all of the forces acting on the cart as it is pulled up the ... | |
| Electricity | 3/14/2009 |
| Q: Can you please help me with Numerical response 8 and multiply choice question 14-16 on this site: ... A: 8) To find the number of excess electrons divide the charge of the oil drop by the charge of a ... | |
| light | 3/13/2009 |
| Q: could you help me with this? when astronomers observe a supernova explosion in a distant galaxy, ... A: Of course! If the different colors [frequencies] of light traveled at the different speeds they ... | |
| Algebra Physics | 3/13/2009 |
| Q: A father pulls his 25-kg daughter on a 5-kg sled across a snowy field. If the father pulls on the ... A: First make a freebody diagram. In this case there should be 3 forces: a normal force of the ground ... | |
| Magnetic Fields | 3/12/2009 |
| Q: A particle undergoes uniform circular motion of radius 12.5 micronmeters in a uniform magnetic ... A: Because this is a charged particle moving in a circular path this is a Newton's 2nd law problem ... | |
| Fan with louver | 3/11/2009 |
| Q: I have a freezing unit with 4 fans. The fans are 35" in diameter. I believe the rotation of the ... A: Depends on what you are trying to achieve! If you are looking for maximum air flow leave the louvers ... | |
| Physics | 3/10/2009 |
| Q: My Question is attached. I tried to solved by finding tension force and then find the theata, but i ... A: a. The angles will be the same! If you make a force diagram for either ball you will get a vertical ... | |
| Physics problem | 3/10/2009 |
| Q: A tank that is 62 meters away is approaching you at a speed of 6 m/s. Your cannon currently is set ... A: To solve this problem you will need to calculate the position of both the tank and the projectile ... | |
| physics | 3/8/2009 |
| Q: A wheel's uniform angular acceleration is constant. Initially its angular velocity is zero. During ... A: The thing to be aware of when doing rotational motion is that the relationships among the variables ... | |
| Thermodynamics | 3/6/2009 |
| Q: I taught AP B Physics for 30 years and am now retired but still tutoring. This question was asked by ... A: Seems pretty pathetic! Is it possible that the overall efficiency of electrical power delivery is ... | |
| help plz | 3/6/2009 |
| Q: I’ve some questions Can u help me with them please? Q1. One car travels due east at 40Km/h, and ... A: Q1. No! Since velocity is a vector both direction and magnitude matter. For example, suppose that ... | |
| Orbital Physics problems | 3/4/2009 |
| Q: recently my physics class has been working on problems concerning the periods of planets and other ... A: If an asteroid is orbiting the sun, it is moving in a circular path and is, therefore, following ... | |
| motion | 3/3/2009 |
| Q: i've several Qs can u help me plz!! Q1. A horse canters away from its trainer in a straight line, ... A: Q1. The issue here is the difference between "speed" and "velocity". Speed is "distance" divided by ... | |
| mechanics | 3/3/2009 |
| Q: A beam AB 5m long is supported at A & B carries two point load W1 and W2 of 3N & 5N which are 1m ... A: I am making the following assumptions: Force A is upwards at the left end Force B is upwards at the ... | |
| Oscillations | 3/2/2009 |
| Q: A solid sphere of radius r is placed at the bottom of a spherical bowl of radius R.When pushed ... A: Good point! If you apply this, the restoring force F becomes: F=m*g*x/R-Ff While the frictional ... | |
| physics problem | 3/2/2009 |
| Q: A 1500 kg car can accelerate from rest to 72 km/hr in 8.0 sec. What is the net force acting on the ... A: This problem can most easily solved by making use of the "impulse" equation - a variation on ... | |
| Physics | 3/1/2009 |
| Q: As shown below, two blocks on an inclined plane are connected to each other by a light string ... A: The freebody diagram for this system should include the following forces: m1: Fg1*sin(Q) [the ... | |
| Oscillations | 2/27/2009 |
| Q: A solid sphere of radius r is placed at the bottom of a spherical bowl of radius R.When pushed ... A: Tough question that I have never come upon before! Here is my analysis. As the ball is displaced ... | |
| physics | 2/26/2009 |
| Q: an object with a mass of 10kg slids upwards on a slippery vertical wall. a force of 60 N acts at an ... A: I assume from the wording of the problem that the vertical surface is frictionless. I am likewise ... | |
| Momentum | 2/26/2009 |
| Q: Two particles of mass m1 = 1.4 kg and m2 = 2.3 kg are traveling with velocities v1 = 4.7 m/s, and ... A: Since momentum is a vector quantity you will need to find the momentum of each object separately and ... | |
| Physics homework help | 2/25/2009 |
| Q: Please help to show me how to do this problem. Two blocks, one of mass 5.0 kg and the other of ... A: This is a Newton's 2nd Law program where the sum of the external forces SF acting on the system will ... | |
| problem | 2/23/2009 |
| Q: a hockey ball of mass 200g travelling at 10m/s is struck by a hockey stick so as to return it along ... A: Momentum is equal to the product of mass and velocity and is a vector quantity. The incoming ... | |
| Conservative Energy forces | 2/21/2009 |
| Q: 1) A woman carries a large bucket of water to the top of a 40m tower at a constant upward speed. The ... A: 1) Seems to me that is this first problem you should be able to determine the work done by the ... | |
| physics | 2/20/2009 |
| Q: A sailboat is moving at a constant velocity of 8 km/h eastward.Describe two opposing forces acting ... A: In order for the boat to move forward at a constant speed the force of the wind acting on the boat ... | |
| Work Done | 2/20/2009 |
| Q: A crate of mass 28 kg is pushed up a ramp by a person, at a 30 degree angle. Assume the coefficient ... A: Work done is equal to the force required to move the object times the distance the object is moved. ... | |
| magnetism | 2/19/2009 |
| Q: Why are nickle and iron magnetic? A: All materials fall into three different categories with respect to magnetism: ferromagnetic, ... | |
| auto accident-How fast? | 2/19/2009 |
| Q: How fast does a 1993 acura weighing approximately 2560 lbs have to be going to hit a back wheel on ... A: I am sure that this is not a complete analysis, but here is at least a partial solution. First ... | |
| charges in particles | 2/17/2009 |
| Q: what is actually the meaning of charges? a proton has positive charge and an electron has a negative ... A: I can't really say WHY particles have charge, only that they do. NO ONE really knows why! Charge is ... | |
| Batteries | 2/16/2009 |
| Q: I was just wondering, when 3 identical cells are connected in series across a filament, in which ... A: If three identical cells are connected in series with a light bulb they should all discharge at the ... | |
| specific gravity | 2/15/2009 |
| Q: I am studying for my Marine engine driver grade 2 (MED 2)certificate and I am stuck on a few ... A: Specific gravity just refers to how the density of something compares with the density of water ... | |
| Weight vs Engery | 2/14/2009 |
| Q: If you have a large box full of Canaries(birds) on their perch and place this on a scale and weight ... A: The weight of the box will be the same whether the birds are flying or not! The only way that the ... | |
| Circular Motion | 2/13/2009 |
| Q: A car is travelling with a constant speed of 27 m/s. The car is equipped with 205/65 R15 tires that ... A: The interesting thing about this problem is that the centripetal acceleration of the stone lodged in ... | |
| Circular Motion | 2/12/2009 |
| Q: In recent years, a number of nearby stars have been found to possess planets. Suppose, the orbital ... A: This is a Newton's 2nd Law problem, the sum of the forces acting on an object is equal to the mass ... | |
| Inertia | 2/11/2009 |
| Q: If a car travels in a circular path at constant speed, is the motion of the car Inertial Frame of ... A: In order for a frame of reference to be "inertial" there can be NO accelerations! Since a car ... | |
| Hammer Rotation Puzzler.??? | 2/11/2009 |
| Q: .. Below is a link that shows a blond Russian lady Hammer thrower (ther are about 4 other ... A: I think, from looking at the video, that your observations are due primarily to the positioning of ... | |
| simple math | 2/10/2009 |
| Q: I need to know the impact force of a 1 Kg dropped 1m please, I am struggling , would appreciate help ... A: The impact force of the dropped mass depends on how long it takes to stop the mass when it contacts ... | |
| charged particles | 2/10/2009 |
| Q: How do caheged particles lose their charge? Is it possible to place charged particles in a container ... A: Innately charged particles do not lose their charge! Electrons and protons cannot lose there charges ... | |
| physics NYC - waves | 2/9/2009 |
| Q: The pendulum of a pendulum clock consists of a 0.99m long rod with a bob of mass 0.40kg. the ... A: The basic approach of this problem will be to use energy conservation. As the pendulum swings ... | |
| newton's2nd law | 2/8/2009 |
| Q: Standing on an stationary elevetor,there is no net force as the normal reaction=my weight.The cables ... A: Both you and the elevator are being accelerated separately by the same planet! When in freefall you ... | |
| Spaghetti | 2/6/2009 |
| Q: today i decided to make myself some spaghetti i boiled some water in a pot with about 10 inch ... A: Fluid convection! As the flame below the pot heats the water in the center of the pot, the water ... | |
| Newton's 2nd Law | 2/4/2009 |
| Q: Recently I was tobogganing with my little brother. After racing to the bottom of the hill (which I ... A: Forgetting about rolling for a moment, when you toboggan down the hill, the mass, in general, will ... | |
| Third Law | 2/2/2009 |
| Q: I cannot lift myself up by pulling on my own hair but I can pull myself up a rope tied to the ... A: When you pull up on your hair, your hair pulls down on your hand! When you pull down on a rope ... | |
| Harmonics | 2/2/2009 |
| Q: A two end open pipe organ's 5th harmonic produces a frequency of 3 beats per second with a tuning ... A: If there is a beat frequency of 3Hz, the resonant frequency of the organ pipe must either be 3Hz ... | |
| Correspondence Physics | 2/1/2009 |
| Q: Sir, I am sure you are watching the Superbowl this afternoon, but this far away member of the ... A: In my experience physics almost always needs a teacher - even for the best of students. Physics can ... | |
| physics | 1/29/2009 |
| Q: A 1.60-m-tall girl throws a football at an angle of 41.0 degrees from the horizontal and at an ... A: All two dimensional kinematics problems are solved in the same way! In kinematics there are six ... | |
| Banked Curves | 1/29/2009 |
| Q: Is there still friction -static or kinetic- present even when the highway is banked at an angle at ... A: If the curve is banked so that no friction is required, then there will be no friction! How could it ... | |
| Physics - Balanced Forces - Resolving Resultant Forces | 1/27/2009 |
| Q: 1) A point object of weight 6.2N is acted on by a horizontal forced of 3.8N. Calculate the resultant ... A: Since these two vectors are perpendicular you can find the resultant by using the Pythagorean ... | |
| physics | 1/26/2009 |
| Q: A 1500 kg car traveling at 90 km/h east collides with a 1000 kg car traveling at 60 km/h south. The ... A: The generic solution for any momentum conservation problem is given by: m1*v1+m2*v2=m1*v3+m2*v4. In ... | |
| Physics problem .. please step by step | 1/26/2009 |
| Q: A toy rocket, of mass 0.12 g, achieves a velocity of 40 m/s after 3.0 s when fired straight up. What ... A: First, let me say that I am assuming that the mass of the rocket is 0.12kg or 120 grams, not 0.12 ... | |
| physics/collisions | 1/25/2009 |
| Q: two identical vehicles are zooming at each other at equal but opposite speeds and they crash head ... A: Since these two vehicles have the same mass and opposite velocities, the final velocity of each ... | |
| should we spend time in the sun | 1/24/2009 |
| Q: hi i am writing to see if you can should we spend time in the sun i am doing it at school and i am ... A: There are two very different aspects to this question! On one hand the ultraviolet light given off ... | |
| Does surface area effect friction when mass stays the same? | 1/23/2009 |
| Q: Does surface area effect friction when mass stays the same? Say for hard plastic wheels on hard wood ... A: Contrary to your intuition, surface area does not directly affect the frictional force between two ... | |
| Pulley | 1/22/2009 |
| Q: Consider two masses m1 and m2 connected by a thin string in opposite ends on a pulley. Assume the ... A: This problem is a Newton's 2nd problem: SF=m*a where SF is the sum of the external forces acting on ... | |
| freeze point for water under pressure | 1/21/2009 |
| Q: Is there a chart showing at what temperature water will freeze under pressure? For example, at zero ... A: If you go to http://www.lsbu.ac.uk/water/phase.html you will find a graph plotting the melting point ... | |
| Thermodynamics | 1/20/2009 |
| Q: How will you explain that the efficiency of a heat engine cannot be 100% in terms of heat absorbed ... A: In order for a heat engine to work you need two reservoirs at different temperatures. Consider, for ... | |
| an improvised hot air ballon | 1/19/2009 |
| Q: why does the hot air ballon flew when you just use candle and plastic? What area in physics does it ... A: Hot air balloons work because the density of hot air is much less than the density of cooler air! ... | |
| for physics | 1/18/2009 |
| Q: What was wrong with Newton's corpuscular theory of light? A: Perhaps not as much as you might think! Throughout the 17th, 18th and 19th centuries a lot of effort ... | |
| Overall wieght calculation | 1/17/2009 |
| Q: If a motorcycle is travelling at 40mph and weighs 214kgs and collides into an object without and ... A: The answer to this question is determined by two factors: how long did the collision take and what ... | |
| Elasticity | 1/17/2009 |
| Q: Why Rubber does not obey Hook's Law though it possesses elasticity? A: Whether or not a substance/object obeys Hooke's Law depends on what the object is made from and its ... | |
| Electric field within wire | 1/16/2009 |
| Q: If I have a wire and use a battery to apply a potential difference between the two ends, do I get an ... A: Absolutely! Why would the electrons move through the wire in the absence of a force. After all, the ... | |
| global warming | 1/10/2009 |
| Q: In your expert opinion, what effect does melting ice cover (in Greenland, Arctic,Antarctic, etc.) ... A: I a not really an expert in this field, however, there are a number of things that a physicist can ... | |
| Physics | 1/7/2009 |
| Q: A hockey player is standing on his skates on a frozen pond when an opposing player, moving with a ... A: This is a kinematics problem that requires you to set up two data tables: one for the first skater, ... | |
| A tough one (of 2) | 1/5/2009 |
| Q: I see you "have a particular interest in modern physics topics." That's good, because another expert ... A: I think the problem here is that you are assuming a mass density of the universe that is MUCH higher ... | |
| non-ferrous metal | 1/4/2009 |
| Q: James, I have a twenty-five foot tall Aluminum light pole in my Pennsylvania yard. It was a former ... A: Your flagpole is a "simple harmonic oscillator" with a relatively high "quality value"! What does ... | |
| Physics | 1/2/2009 |
| Q: A 4.3 g bullet leaves the muzzle of a rifle with a speed of 338 m/s. What force (assumed constant) ... A: First treat the problem as a kinematics problem to determine the acceleration of the bullet. There ... | |
| Creation of energy | 1/1/2009 |
| Q: If energy cannot be created, why in a hot air generator prototype which uses a friction-adiabatic ... A: I am not exactly familiar with what you are referring to, but when you compress a gas adiabatically ... | |
| magnetism | 12/30/2008 |
| Q: I would like to convert the strength of magnets that are measured in pounds (the kind you buy in the ... A: You cannot get from one to the other in any simple way. However, the magnetic field strength of such ... | |
| Water and Gravity | 12/30/2008 |
| Q: I'm trying to figure out what the effect of higher gravity/lower gravity would be on water. For ... A: If gravity was 2x Earth gravity: Surface temperature would remain the same, however, that surface ... | |
| how does terminal velocity vary with the shape of object | 12/29/2008 |
| Q: I wanted to ask if terminal velocity will vary if I use objects of different sizes. Example-which ... A: Shape matters a great deal and is not easy to model. However, if the shape remains the same but the ... | |
| internal resistance of battery | 12/28/2008 |
| Q: What factors are affected inside a battery that leads to a change in internal resistance when the ... A: I think that you and I are using the word "capacity" very differently. It is my understanding that ... | |
| Mechanics | 12/27/2008 |
| Q: This question was on my final for mechanics. A 5 kg block rests on a frictionless hill angled at a ... A: As I understand your question this is a system at equilibrium. If so, the force of gravity on the 15 ... | |
| internal resistance of battery | 12/26/2008 |
| Q: What factors are affected inside a battery that leads to a change in internal resistance when the ... A: As the temperature of a battery is increased the rate of the chemical reaction increases which in ... | |
| internal resistance of battery | 12/26/2008 |
| Q: What factors are affected inside a battery that leads to a change in internal resistance when the ... A: Batteries work because there is a chemical reaction within the battery that does work on charge ... | |
| Electricity | 12/25/2008 |
| Q: Sir will you pls explain me how a resistance box works? A: I can't speak for all resistance boxes, but the ones that I use in my classroom have carbon ... | |
| Blu-Ray laser | 12/24/2008 |
| Q: Why are blu-ray lasers higher power than ordinary CD/DVD player lasers? Is this because the ... A: It is not a matter of more energy! Rather it is a matter of wavelength! Blue light has a smaller ... | |
| electromagnetism | 12/21/2008 |
| Q: Can you tell me please, why a neon tube traversed by an electric current doesn't attract ... A: The current in a neon tube is AC rather than DC. This means that the average field near the neon ... | |
| ladder problem. | 12/19/2008 |
| Q: I'm trying to calculate how high a 490N person can climb up a ladder before it starts to slide out ... A: This problem requires the application of Newton's 1st Law with application of the two conditions ... | |
| Dark Matter | 12/18/2008 |
| Q: What is dark matter and what has the most recent research into the subject revealed about its ... A: Dark matter is matter that does not radiate detectable radiation and as a result is seemingly ... | |
| kinetic energy | 12/18/2008 |
| Q: what is the diffrence between kinetic energy and work and how is that there is a kinetic energy for ... A: Work occurs when a force is applied and as a result motion occurs - the force being applied must be ... | |
| electric potential | 12/17/2008 |
| Q: what is meant by electric potential and what is the negative work A: Electric potential is a lot like gravitational potential. If work is done to lift a box onto a ... | |
| how does color affect heating by absorption of light | 12/15/2008 |
| Q: i am in the 8th grade and i am doing a science fair project on the above subject and didn't know if ... A: Generally speaking, the darker the color, the more light energy that is absorbed and converted into ... | |
| Coulomb's Law | 12/14/2008 |
| Q: "Hi, I'm having alot of trouble understanding the basics of Coulomb's law. For one thing I can't get ... A: The electrostatic force between two charged particles is given by F=k*q1*q2/R^2. This means that the ... | |
| Force distance traveled in air question | 12/13/2008 |
| Q: This is a 9/11 towers physics question. I am trying to remember my physics and was wondering if you ... A: From an energy conservation point of view this is entirely possible. Let me give you an example! ... | |
| Torque Calculation | 12/11/2008 |
| Q: How do I calculate the torque required to turn a shaft? I know torque = Force x radius but I do not ... A: You will need to find out how much force is needed to rotate the drum first. The torque required ... | |
| physics investigatory project | 12/8/2008 |
| Q: what is the easiest physics investigatory project to be done? our teacher have told us that we ... A: Where can I begin? There is literally an infinite number of choices since physics is about ... | |
| motion | 12/7/2008 |
| Q: Kovalcin,here is my physics problem: An airplane with a speed of 200 mi/h is heading 30.0 degrees ... A: You are correct that the problem is a vector addition problem. Because the velocity of the airplane ... | |
| Paperweight/Fluids | 12/4/2008 |
| Q: James, I have this problem that I really don't know how to do. I tried this 2 -3 times but I like ... A: When immersed in a liquid the decrease in apparent weight is equal to the weight of the displaced ... | |
| area of flow of electron in a conductor | 12/3/2008 |
| Q: From where the electrons flow in a conductor ?from conductor's suface or under its surface ? A: The electrons flow throughout the interior of the conductor. That is why the resistance of a wire is ... | |
| PHYSICS 11 QUESTION | 12/2/2008 |
| Q: what is the maximum acceleration a car can undergo on level ground if the static coefficient of ... A: The only force available to accelerate a car on a horizontal surface is the force of friction. ... | |
| kinetic energy.. | 12/2/2008 |
| Q: i was wondering if u can help me with these questions 1) In pool, when the cue ball hits another ... A: When one pool ball strikes another energy is not eh only thing to consider. More importantly is the ... | |
| Electrolysis cleaning | 12/1/2008 |
| Q: How/why does the electrolysis process clean corrosion off of things? A: In electrolysis some of the metal is dissolved by the flow of current. As this metal is dissolved it ... | |
| conductors | 11/30/2008 |
| Q: if there is a charge placed (not exactly in center), of a hollow spherical conductor, then how will ... A: Any Gaussian surface surrounding the charge within the hollow spherical shell will predict an ... | |
| PHYSICS | 11/29/2008 |
| Q: We know 2+2 is 4, but can physics present a working model as to how a cell upon cenception becomes ... A: The most recent estimate is that the total mass-energy of the universe is very close to zero - and ... | |
| conductors | 11/28/2008 |
| Q: if there is a charge placed (not exactly in center), of a hollow spherical conductor, then how will ... A: No matter where the charge is placed within the conducting sphere the electric field lines outside ... | |
| PHYSICS | 11/26/2008 |
| Q: We know 2+2 is 4, but can physics present a working model as to how a cell upon cenception becomes ... A: There is no implication at all that when a cell divides that something comes from nothing. You are ... | |
| Egg drop- | 11/26/2008 |
| Q: We have been asked to build a vehicle that would safely carry an egg from a height of fifty feet. ... A: The goal in this kind of activity is to make the time of the actual collision take the longest ... | |
| buoyancy | 11/25/2008 |
| Q: Does a sunken ship sitting on the ocean floor have a buoyant force on it? I'm certain this relates ... A: The buoyant force on a submerged object is equal to the weight of the displaced liquid. For example ... | |
| Help on inclined planes | 11/23/2008 |
| Q: I need some help in a physics lab report that I am writing. In our lab, we wanted to calculate the ... A: The coefficient of friction mu would equal the tangent of the angle of the incline a ONLY if the ... | |
| Help on inclined planes | 11/22/2008 |
| Q: I need some help in a physics lab report that I am writing. In our lab, we wanted to calculate the ... A: You actually already seem to be on the right track. If a mass is to pushed up an inclined plane at a ... | |
| Flu | 11/21/2008 |
| Q: Mr. James I have doubt on this question. Ive been trying this fro quite some time, but i dont know ... A: The weight of an object is equal to the mass m of the object times the gravitational force constant ... | |
| Physics-Pressure etc. | 11/21/2008 |
| Q: Hey Sir, Hope your doing alright. I have a question I need help on. I request you to please take a ... A: Assuming that the flat side of the brick is facing down, first calculate the area of the brick in ... | |
| Magnet Powered rotation | 11/18/2008 |
| Q: Referring to the previous question, you said "No such motor is possible" could you tell me what is ... A: What is impossible is the construction of a motor [magnetic or otherwise] that is capable of ... | |
| Magnetic Motors | 11/17/2008 |
| Q: I have a question - do magnetic motors - ie magnet powered motors or devices violate the laws of ... A: I watched the video and am sorry to say that it is wishful thinking only! No such motor is possible. ... | |
| Magnetic Motors | 11/17/2008 |
| Q: I have a question - do magnetic motors - ie magnet powered motors or devices violate the laws of ... A: I am still a bit confused by your question because ALL electric motors are "magnet motors"! I ... | |
| Optics | 11/16/2008 |
| Q: Sir, I'd like to know why objects light in colour radiate the light falling on them while dark ... A: Whether or not a surface absorbs or reflects light depends on the nature of the electron orbitals in ... | |
| Magnetic Motors | 11/16/2008 |
| Q: I have a question - do magnetic motors - ie magnet powered motors or devices violate the laws of ... A: Of course not! If they did they wouldn't work. The "Laws of Physics" are NOT optional! What is it ... | |
| Water dipole | 11/15/2008 |
| Q: Why is water a polar molecule / dipole with the hydrogen atoms in one end of the water molecule? I ... A: What you are ignoring is that atoms are held together not by just an electrostatic force between the ... | |
| Physics | 11/14/2008 |
| Q: A proton (m = 1.67 x 10-27 kg) traveling at 300 with respect to a 5.2 mT magnetic field lines ... A: The magnetic force on a moving charged particle is given by: Fm=q*VxB where q is the charge of the ... | |
| force | 11/13/2008 |
| Q: Where do forces come from? And can a body, in and of itself, possess a force as it possesses other ... A: There are actually very few forces in nature: the electromagnetic [or electroweak] force - the force ... | |
| Effects of taking x-ray twice in a month or week | 11/12/2008 |
| Q: What are the effects of taking x-ray twice in a month or week? What if after doing so, I experience ... A: Unless this is a very special situation, the dose received from each xray is VERY low compared to ... | |
| Sound Phenomena and the Doppler Effect | 11/10/2008 |
| Q: This is the last question for a couple of weeks, I promise =O] Bats emit sounds of frequencies ... A: The frequency heard from a moving source and by a moving observer is given by: ... | |
| Linear Momentum and Collisions | 11/9/2008 |
| Q: A projectile that is fired from a gun has an initial velocity of 90.0km/h at an angle of 60.0 ... A: One of the alternative interpretations of momentum conservation is that in an isolated system the ... | |
| Momentum | 11/9/2008 |
| Q: A pendulum consists of a mass M hanging at the bottom end of a massless rod of length l, which has a ... A: This problem has 2 parts. In the first part momentum conservation is used to determine the velocity ... | |
| Angle of Third Class Lever | 11/8/2008 |
| Q: A 1200 cm long third class lever is placed so that one end is on a flat surface (ie. the floor) and ... A: I believe that you are ignoring the force exerted by the fulcrum acting on the lever arm. This will ... | |
| formula for lift | 11/7/2008 |
| Q: I have done a hot air balloon experiment and now I'm trying to find it's lift. i have got: Lift = CL ... A: I do not see that you actually have the lift! The lift of a balloon would be equal to the difference ... | |
| Angle of Third Class Lever | 11/5/2008 |
| Q: A 1200 cm long third class lever is placed so that one end is on a flat surface (ie. the floor) and ... A: This problem is a torque problem. From a practical point of view this means that for a system to be ... | |
| Physics - Energy/Momentum | 11/4/2008 |
| Q: A 2 kg block is compressed by a spring of force constant 300 N/m by 4.5 cm. If the block-spring ... A: The first part of this problem can be solved using the concept of energy conservation - the total ... | |
| Physics - Energy/Momentum | 11/4/2008 |
| Q: A 600g basketball is moving 10m/s when it hits a blackboard at 90degrees. The ball bounces off at a ... A: This problem uses the "impulse" equation, which is a form of Newton's 2nd Law written in terms of ... | |
| Physics | 11/2/2008 |
| Q: A daredevil decides to jump a canyon of width 10 meters. To do so she drives a motorcycle up an ... A: All two dimensional kinematics problems can be solved using the exact same procedure; identify the ... | |
| kinematic formulas | 11/2/2008 |
| Q: my teacher gave me these to formulas Vf=Vi+at and deltaX(DX)=Vit+.5at^2 i am supposed to use ... A: Start with the two kinematics equations: Df=1/2*a*t^2+Vo*t+Do and Vf=a*t+Vo Solve the velocity ... | |
| projectiles/ | 10/31/2008 |
| Q: how fast must a projectile moving horizontally travel so that the curve it follows matches the curve ... A: Turns out that there is a surprisingly easy way to solve this problem! If the projectile is to ... | |
| braking or turning? | 10/30/2008 |
| Q: a car is approaching a wall at V m/s velocity, is it better to turn the car keeping the velocity ... A: The real question is "What acceleration will be required to avoid hitting the wall?". So let's solve ... | |
| hints to solve this problem | 10/29/2008 |
| Q: I'm stuck with this question so if possible I need some hints to start solving it: A light string ... A: The tension in a string causing an object to move in a circular path is given by: Fc=m*v^2/R. In ... | |
| braking or turning? | 10/29/2008 |
| Q: a car is approaching a wall at V m/s velocity, is it better to turn the car keeping the velocity ... A: I don't think the problem can be answered the way you have asked it. It all depends on whether or ... | |
| Question | 10/28/2008 |
| Q: how r ya... i having trouble with this problem. if you would please take a look at it and explain , ... A: The momentum of the blood will have to be equal in magnitude to the momentum of the body: ... | |
| Need HElp! | 10/28/2008 |
| Q: Hey Sir, I need your help real quick on this problem. I hope you can help, I tried this problem a ... A: In a closed system the total momentum remains constant. In this case, since there are two objects, ... | |
| Physics of sound | 10/27/2008 |
| Q: I'm so stuck. I just don't know where to start please help :0 What are the first four resonant ... A: The smallest part of a sound wave that will resonate within a tube either open at both ends [an ... | |
| physics | 10/27/2008 |
| Q: An airplane starts from rest and accelerates at a constant 3.10 m/s2 for 31.0 s before leaving the ... A: All one dimensional problems of this type can be solved in the exact same way. All kinematics ... | |
| Momentum | 10/24/2008 |
| Q: Hey Mr. James, I tried this problem a couple of times. I did the momentum formula and stuff, and ... A: This problem involves center of mass. As long as there are no unbalanced external forces acting on a ... | |
| Earth and ocean | 10/23/2008 |
| Q: We know that when a tank is filled with water ,the level of the water (waterlevel)is a plane(surface ... A: I have attached a diagram that I hope will help. Each arc has the same length, but notice that for ... | |
| Tension | 10/21/2008 |
| Q: I was just wondering if you could explain the concept of tension to me. Is it correct that if you ... A: The stretch of the rope should not matter except in the sense that the rope may, if fact, have some ... | |
| Pendulum force | 10/19/2008 |
| Q: I am a junior high school student and I need to have a formula that will tell me the tangential ... A: The force exerted by the bob during a collision will depend on how long the collision takes to ... | |
| Magnet Car | 10/19/2008 |
| Q: So I asked this question to another Expert, and he couldn't seem to answer. I asked whether or not a ... A: This won't work because there is NO unbalanced acting on the car in this situation. Sure, the magnet ... | |
| physics (i think it is) | 10/18/2008 |
| Q: How can you make liquid nitrogen and how come it jumps up and down? A: Liquid nitrogen is made by using a process very similar to that which is used in an air-conditioner ... | |
| Pendulum force | 10/17/2008 |
| Q: I am a junior high school student and I need to have a formula that will tell me the tangential ... A: I assume that you don't really mean the "tangential" force at the bottom of the swing because that ... | |
| Calculation Help | 10/17/2008 |
| Q: I have been asked a question which is outside my knowledge, I dont know if you can assist... There ... A: I am making the following assumptions: that there is NO significant frictional force between the ... | |
| How much friction force must the brake apply to the rim to bring the disk to a halt in 3.0 s? | 10/16/2008 |
| Q: The 2.2 kg, 40 cm diameter disk in the figure below is spinning at 380 rpm. How much friction force ... A: This problem is a combination of two distinct different problem types: kinematics and Newton's 2nd ... | |
| Mechanical advantage | 10/16/2008 |
| Q: Kovalcin, I would like to know whether Mechanical advantage could be used to generate power.Whether ... A: Not at all! Simple machines do NOT create energy! All they do is to convert one type of energy into ... | |
| superconductivity | 10/15/2008 |
| Q: i was just wondering if you knew how to get a superconductor higher off a magnetic track? Would ... A: Even in the case of magnetic levitation trains the train only floats a centimeter or so above the ... | |
| bouyancy as a force | 10/14/2008 |
| Q: i have a float a hollow cube 100mm x 30mm x 100mm deep i am using this float to close off an airway ... A: A floating object will follow Newton's 1st Law; if a system is at equilibrium opposite forces must ... | |
| Physics, Kinematics Review | 10/13/2008 |
| Q: I am having difficulty truly understanding how to solve relative motion problems? The professor ... A: a. To head directly across the stream she must aim the boat upstream so that the component of the ... | |
| Forces of Friction | 10/12/2008 |
| Q: I would like to know how to solve this problem. A block accelerates 3.1 m/s^2 down a plane inclined ... A: Unfortunately, there is not enough information given to solve this problem as stated. Since the ... | |
| Coefficient of restitution | 10/12/2008 |
| Q: If you drop a ball on the ground and calculate the coefficient of restitution as the square root of ... A: The component of the ball's velocity parallel to the surface will not cause the ball to collide with ... | |
| black body radiation | 10/11/2008 |
| Q: suppose there is a black body in a room at T temperature and the temperature of the room is T and ... A: Assuming that the surrounding room's temperature remains constant, then your analysis is correct. ... | |
| physics-- projectiles and 2d motion | 10/10/2008 |
| Q: A ball is thrown from the top of a building upwards at an angle of 46 degrees to the horizontal and ... A: All 2 dimensional kinematics problems can be solved in the same way. First of all, any kinematics ... | |
| Coefficient of restitution | 10/9/2008 |
| Q: If you drop a ball on the ground and calculate the coefficient of restitution as the square root of ... A: The coefficient of restitution should only depend on the component of the velocity perpendicular to ... | |
| Hazards of 400 nm lasers? | 10/8/2008 |
| Q: What hazards -- other than thermal burns -- does a 400-nanometer-wavelength continuous [i.e. ... A: By definition a class 4 laser burns skin! The fact that the light is near to ultraviolet does not ... | |
| Weight and Force I think | 10/8/2008 |
| Q: i read this question that Eric A Cornells (Nobel Prize Physics 2001) father teased him with when ... A: I believe that your initial analysis is correct. In order for the bees to remain air born their ... | |
| Physics/mechanics | 10/7/2008 |
| Q: Alright so we've started mechanics and I'm having trouble with alot of the practise questions we've ... A: This problem requires the use to two separate ideas, Newton's 2nd Law, as you have already noted, ... | |
| Electric Field and Application | 10/7/2008 |
| Q: What is the importance/relevance to know the electric field distribution of a electrical apparatus? ... A: Not quite sure about the context of your question, but if the electric field in an electronic device ... | |
| Helium balloons | 10/5/2008 |
| Q: Just curious about the Helium balloons in free air. I saw in 'Nat Geo - What would happen if ?'some ... A: Keep in mind that the Helium balloon is is LIGHTER than air and so, behaves like an ice cube ... | |
| voltage across inductor | 10/4/2008 |
| Q: we performed an experiment on how inductor behaves in R-L series circuit.......... the peak to peak ... A: Since I do not know the exact circuit you are using I can't really answer you question fully. ... | |
| Boiling of water | 10/4/2008 |
| Q: My question is about the changes that water undergoes as it boils. I understand that as water is ... A: The high speed of the molecules is such that the electrostatic bond between adjacent molecules is ... | |
| simple circular acceleration physics | 10/3/2008 |
| Q: So, I have a problem, here it is The rotor (the figure below) is an amusement park ride where people ... A: When you stand along the wall in the Rotor while rotating there are 3 forces acting on you: Fg down ... | |
| Projectile Motion | 10/3/2008 |
| Q: A car needs to jump a river 110 meters wide off of a ramp, if the ramp is raised 5 degrees and the ... A: All problems of this type are solved in the same way! All freefall problems involve 6 different ... | |
| Projectile Motion | 10/1/2008 |
| Q: A ball is thrown from a point 1.0 m above the ground. The initial velocity is 19.6 m/s at an angle ... A: All 2 dimensional kinematics problems can be solved in the same way. First of all, any kinematics ... | |
| physics | 9/30/2008 |
| Q: a force of 80 newtons is exerted on an object on a frictionless surface for a distance of 4 meters. ... A: This problem requires a combination of Newton's 2nd Law [to determine the acceleration] and ... | |
| Newton's Laws of Motion | 9/29/2008 |
| Q: I would like to seek your guidance on the following problem with respect to the concept of inertial ... A: The speed of the lift [elevator in the US] will make NO difference as long as it is constant! ALL ... | |
| Newton's Third Law | 9/29/2008 |
| Q: I would lke to make sure that i finally understand newtons third law. If I am pushing on a marble ... A: What you are describing is not Newton's 3rd Law! The 3rd Law says nothing about other forces acting ... | |
| electricity | 9/28/2008 |
| Q: sir i want to ask that is transformer an inductor? if it is an inductor so wh does not it blocks ac ... A: An inductor is typically made up from a solenoid, a coil whose length is greater than its diameter. ... | |
| physics problem | 9/27/2008 |
| Q: When you lift a bowling ball with a force of 82 N, the ball accelerates upward with an acceleration ... A: To answer this question apply Newton's 2nd Law twice! According to Newton's 2nd Law, the sum of the ... | |
| Your reply on the charged Rod Question | 9/27/2008 |
| Q: Hey, someone asked the following question and you kindly answered in detail, yet, i couldnt ... A: The linear charge density is, as you have noted, equal to the charge divided by the length. But in ... | |
| ELECTRIC CIRCUITS | 9/26/2008 |
| Q: SIR , WE DEFINR ELECTRIC CURRENT AS THE " RATE OF FLOW OF ELECTRONS " . MY QUESTION IS THAT ... A: The flow of electric current actually falls into to different types: drift velocity and propagation ... | |
| Friction | 9/24/2008 |
| Q: When a block rests on a truck that is moving with uniform velocity, the block also moves with the ... A: The underlying assumptions of this problem are not correct as stated. If a truck is moving down the ... | |
| Magnetism | 9/23/2008 |
| Q: 1) How do you determine whether the magnetic force will go into or out of page? What does it mean ... A: The thing that is special about magnetic fields is that the force exerted on a charged particle ... | |
| gravitation | 9/21/2008 |
| Q: why is the gravitational potential enrergy of a body on mass m the surface of earth in the ... A: Since we expect that "universal gravitation" will be applicable everywhere in the universe we have ... | |
| LHC | 9/20/2008 |
| Q: I have read on the CERN website that black holes produced in the LHC could settle in the earths core ... A: I don't know where you read this about mini black holes, but this is not, to the best of my ... | |
| with concept of physics | 9/20/2008 |
| Q: Is the torque changed when a partner on a seesaw stands or hangs from herend instead of sitting? ... A: How you sit or stand on the see-saw does NOT affect the torque exerted. What does matter is WHERE ... | |
| Relative sizes of nutrino and quark | 9/19/2008 |
| Q: According to current theory, which is larger: a neutrino or a quark? Many thanks, Steve A: "Size" may not be the right word, however, quite clearly the total mass-energy of a quark is MUCH ... | |
| momentum | 9/17/2008 |
| Q: Which should be the best on knocking the bear down- a lead bullet or a rubber bullet with the same ... A: Because the density of the lead bullet is greater than the rubber bullet, its cross section will be ... | |
| small electromagnets | 9/14/2008 |
| Q: I have a question about electromagnets I was wondering if you could help me with. How small can an ... A: They can be any size you want. The only real limit is how small of a coil can you turn. Small is ... | |
| gravitation | 9/13/2008 |
| Q: sir few questions on gravitation 1) the gravitational force is inversly proportional to the ditance ... A: 1. Your analysis is correct. 2. It does! But the distance moved by the earth is infinitesimally ... | |
| Falling Objects (neglected air resistance) | 9/13/2008 |
| Q: I am a High School student taking a Physics course. I am stuck in the following question and would ... A: All one dimensional kinematics questions can be solved in the same way. There are 6 possible ... | |
| Visible Neutrino Collisons | 9/11/2008 |
| Q: I am aware that neutrinos can be detected when there is a collison with a regular particle, and a ... A: What is possible and what is likely are very different! The likelihood that you would be looking in ... | |
| Holograms | 9/11/2008 |
| Q: I had an interest in the technology of making holograms of very large areas (outdoors in ... A: I am certainly no expert in all phases of holography, but I do know the basic process. In a typical ... | |
| Particle accelerators | 9/10/2008 |
| Q: In light of recent global news, my question is:- The particle accelerator being used in France to ... A: The accelerator at Cern has been upgraded with new superconducting magnets and many other parts ... | |
| friction | 9/9/2008 |
| Q: sir we were doing this practical in physics of finding the coeeficient of static friction using an ... A: Theoretically, the angle at which the object slides down the incline depends ONLY of the angle of ... | |
| Physics | 9/9/2008 |
| Q: Suppose 0.6 cubic meter of oil is spilled into the ocean. Find the area of the resulting slick, ... A: Treat the oil slick as if it were a pancake where the volume of the pancake would be equal to the ... | |
| Physics: thermodynamics | 9/8/2008 |
| Q: I'm having to do a project on thermodynamics and I was wanting to know; is there thermodynamics on a ... A: I wouldn't use a roller coaster as an example of the application of thermodynamics. Sure there is ... | |
| Mechanics: Motion | 9/6/2008 |
| Q: I had trouble figuring this question out...The answer is supposed to be 5kg but I keep getting 7 kg ... A: Intuitively! If the body is accelerating upward with an acceleration of 4m/s^2 the effective ... | |
| electrons slow down | 9/3/2008 |
| Q: Apparently the motion of an electron around an atom nucleus resembles an endless motion. In other ... A: I know this won't be very helpful, but our model of electrons asserts that electrons, like all ... | |
| alternating current in houses | 9/2/2008 |
| Q: If the electricity current delivered to our houses is an alternating current it should reverse its ... A: The "hot" wire in a circuit is the source of the force [EMF] that pushes and then pulls the ... | |
| Physics | 9/2/2008 |
| Q: How do i calculate the gravitational force between the earth and the moon. F= G m1m1/d2 A: As you have already noted, the force between two masses, m1 & m2, is given by: Fg=G*m1*m2/r^2 where ... | |
| balance and torque | 8/21/2008 |
| Q: i want to ask 1) when we sit on bicycle or a two wheeler which is not parked on its stand, and our ... A: 1. When a bicycle is moving, the wheels are rotating. Rotating wheels have a physics quantity known ... | |
| physics | 8/21/2008 |
| Q: A girl is playing tennis against a wall. She hits hte tennis ball from a height of 0.5m above the ... A: All 2 dimensional kinematics problems of this type can be solved in the exact same way. First of ... | |
| Quick high school physics question | 8/20/2008 |
| Q: I just have a quick question from my high school AP Physics class. I know it is an easy problem and ... A: Your difficulty here is caused by the fact that you are asking the wrong question! The real question ... | |
| gravitation | 8/18/2008 |
| Q: 8 m/s^2) if the earth starts rotating faster around it's axis and if it stop rotating?sir please ... A: The acceleration of gravity at the Earth's surface will, in general, be unaffected by the rotational ... | |
| help | 8/15/2008 |
| Q: a bullet is fired from a rifle, emerging from the muzzle at 340 meters per seconds. it strikes a ... A: I would use kinematics to solve this problem. Since the bullet has lost 10% of its velocity, its ... | |
| Maxwell Equations changed E and B fields | 8/11/2008 |
| Q: Based on what I've read about Electromagnetic waves is that a changing Magnetic (B) field causes a ... A: The magnetic field is determined NOT by the magnitude of the electric field, but by the RATE OF ... | |
| bicycle sprockets | 8/10/2008 |
| Q: Last year I bought a new 17 speed bicycle and have made good use of it. Some of the roads and ... A: Sorry, but things will not work out the way you envision. The purpose of either the sprocket system ... | |
| Momentum and collision question | 8/9/2008 |
| Q: I hope you can help me find the proper simple equation that can help my students find the following ... A: Let me try to answer this question using a different set of numbers. Let's assume that the ... | |
| physic -- friction | 8/8/2008 |
| Q: What is the direction of friction acting on a ball rolling in clockwise direction? ANSWER: In ... A: If the ball is rolling towards the right on a level, horizontal surface, the frictional force on the ... | |
| Relativity | 8/8/2008 |
| Q: So a rocket is traveling at a constant speed of from above half to the actual speed of light. From ... A: Not at all! For a moment let's assume that the two rockets are heading in opposite directions at ... | |
| physic -- friction | 8/7/2008 |
| Q: What is the direction of friction acting on a ball rolling in clockwise direction? A: In general the frictional force will tend to act opposite to the direction of motion of the ball as ... | |
| centre of mass | 8/5/2008 |
| Q: sir can you please explain me what is meant by centre of mass and how is it different from centre of ... A: The center of mass is that one point on an object where a single force can be applied to that object ... | |
| please help me to answer this problem | 8/4/2008 |
| Q: 23.0) a closed system containing a gas undergoes a reversible compression process in which the ... A: In a constant pressure problem the work done is equal to the pressure times the change in volume: ... | |
| please help me to answer this problem. | 8/3/2008 |
| Q: 18.0) a 1600-kg car is stopped at5 a traffic light proceeding in direction up a 15 degree hill. The ... A: Average power is equal to the work done divided by the time required to do the work. In this case ... | |
| please help me to answer this problem. | 8/3/2008 |
| Q: 17.0) if a car produces 21 kW when moving with a velocity of 60 km/hr. determine a) the resisting ... A: Power is equal to the product of force and velocity: P=F*v That means that in this case the ... | |
| Negative VelocitY? | 7/13/2008 |
| Q: To whom it may concern, Some time after I graduated high school I was at work and bored so I ... A: There is a perfect video on you tube that addresses this question exactly at ... | |
| angular momentun | 7/10/2008 |
| Q: I think I understand the conservation of angular momentum but need clarification on a particular ... A: The only issue here is whether the torque causing the orbiting planet to change its angular velocity ... | |
| Potential Energy | 7/5/2008 |
| Q: A student lifts a 10N box one meter above the floor, walks 10m with the box and then sets it down ... A: The answer is zero! Gravitational potential energy depends on only 3 things: the acceleration of ... | |
| Physics-Matching | 7/3/2008 |
| Q: 1.motion 2.chemical 3.rate of doing work 4.unit for power 5.unit for work A.joule B.watt C.potential ... A: 1. Effort is the force put into the machine. Given in this problem. 2. The IMA is equal to the ratio ... | |
| Physics True or False | 7/2/2008 |
| Q: 1.Teflon,soap,and graphite are all lubricants. 2.tires are designed to increase rolling friction and ... A: 1. True - All three substances are designed to reduce the frictin between two surfaces. 2. False - A ... | |
| Physics True or False | 7/1/2008 |
| Q: 1. Wind has the ability to do work 2.if you push hard against a wall, you are doing work 3. THe ... A: In order for work to occur in the physics sense two conditions MUST be met: a force must be applied ... | |
| electricity | 6/30/2008 |
| Q: sir, recently i came across the thevenins theorem and nortons theorem i cdnt understand what is a ... A: A constant current source means exactly what it says - the current output will remain constant no ... | |
| step down and step up pulley | 6/30/2008 |
| Q: I have a motor that turns at 1700rpm and I need a pulley to increase the rpm to around 10000. the ... A: The angular velocity will be inversely proportional to the radii of the 2 pulleys. The linear ... | |
| Projectile Motion | 6/27/2008 |
| Q: I am stumped by this seemingly simple physics problem. I have looked around a lot on the web, but it ... A: Actually, this problem and virtually ALL two dimensional problems of this type can be solved in the ... | |
| sound and pitch? | 6/25/2008 |
| Q: .. I have a couple of problems that I need help solving and was hoping you can help me. 1. how do ... A: 1. For an open tube, resonance will occur when the length tube is any integer multiple of 1/2 ... | |
| pressure of a knife | 6/23/2008 |
| Q: I read that a knife cuts with a 1000 pounds/square inch. I'm not sure what that means since the edge ... A: Suppose that you took a pin whose time was a circle with a diameter of 1/100 of an inch. In this ... | |
| physic - cooling | 6/22/2008 |
| Q: If I were to place a tube between the water supply to the swamp cooler and the swamp cooler, having ... A: It would be cooler and this is the reason for using ground source water for cooling when practical. ... | |
| RC Circuits | 6/16/2008 |
| Q: what are the equations to find the voltage across a resistor and capacitor of a RC Circuit in ... A: The current through [not across] circuit elements in series will be constant because, of course, ... | |
| RC Circuits | 6/16/2008 |
| Q: what are the equations to find the voltage across a resistor and capacitor of a RC Circuit in ... A: Assuming that you start with an uncharged capacitor and you close a switch in series with the ... | |
| PHYSICS: RC Circuits | 6/15/2008 |
| Q: what are the equations to find the voltage and capacitance of a RC Circuit in series? The circuit ... A: You will need to connect the capacitor in parallel with a resistor and led connected in series. The ... | |
| Physics | 6/14/2008 |
| Q: Kovalcin, I am wondering about the behaviour or fluids such as water of fuel in the back of ... A: If the truck is freely accelerating down a hill not much would happen at all - I would expect the ... | |
| electrical | 6/12/2008 |
| Q: A 100 W, 200V bulb is connected to 100 V supply. what will be the wattage? A: Since this bulb is rated at 100 watts at 200 volts and since power equals voltage squared divided by ... | |
| Magnet only pushes in one direction | 6/10/2008 |
| Q: http://www.youtube.com/watch?v=xb8wwkdtz0M Can you explain this ? A: It is difficult to tell exactly what is going on, but let me make several points. 1. There is no way ... | |
| about electric field | 6/9/2008 |
| Q: show that of a charged particle in a transverse uniform electric field is parabolic A: If a charged particle moved horizontally through a vertically oriented electric field the resulting ... | |
| kinetic energy | 6/9/2008 |
| Q: I am shown a graph as described: left - Force (N) bottom - Displacement (m) The graph starts at 0 ... A: The kinetic energy gained by the object will be equal to the work done. [This is called the ... | |
| units | 6/8/2008 |
| Q: Sir few very basic questions related to units in meausrement as we hav been introduced to units in ... A: One of the key issues of the metric system is to provide units that can easily be determined by any ... | |
| Electricity | 6/6/2008 |
| Q: Please trace the flow of electrons from the stepdown transformer at the pole outside my house to the ... A: First of all, electrons do NOT flow from the pole into your house and back to the pole at all! All ... | |
| Ask Heat Transfer Question | 6/6/2008 |
| Q: I have 3000L hot water with temperature 90 Celcius in a tank with cap. 4000L. I put 50 mm thick ... A: Sorry, I hit the wrong button. As stated I can't figure out what the question is. Please check your ... | |
| magnetism | 6/4/2008 |
| Q: A DC current flows in a stright wire,a magnetic field is generated aroung its axis according to the ... A: A DC current would NOT produce an electric field! An AC current WOULD generate an electric field! ... | |
| Newton/Einstein in relation to space travel | 6/4/2008 |
| Q: James A fine bottle of whiskey depends upon your answer.:) My friend and I were debating gravity ... A: As far as I know Relativity Theory is not necessary to predict common trajectories for satellites ... | |
| I need help Physics is killin me | 6/3/2008 |
| Q: Here is a questions I need help with: Tarzan, mass 85kg, swings from a tree on the end of a 20m ... A: This is a problem involving the conservation of energy. In a closed system [a system in which there ... | |
| electrostatics? | 6/2/2008 |
| Q: a girl with long(50cm) hair touches the van de graaf generator at a science museum and her hair ... A: I am having a little bit of difficulty picturing exactly what is happening. If I really do ... | |
| Net force | 6/1/2008 |
| Q: I need a little help understanding a homework problem: a car is driving down the road at a constant ... A: For a car going down the highway at a constant velocity, the UNBALANCED force acting on the car must ... | |
| LEDs and electricity. | 5/31/2008 |
| Q: i have a question about electricity and LEDs. I wish to know if there is anything similar to the ... A: One important factor that should be taken into consideration when using an LED; they must always be ... | |
| physics: force | 5/30/2008 |
| Q: I have done this problem up to a certain point but am confused as to how to finish it. Cathy takes ... A: May I suggest that you look at the problem somewhat differently? In order to accelerate the cake ... | |
| Changing shadow sizes - 3rd grade | 5/27/2008 |
| Q: In a third grade activity students are to make a shadow on the wall using an object (tongue ... A: It should not matter whether you move the light or the tongue depressor. What will matter, however, ... | |
| pressure | 5/27/2008 |
| Q: Why do we call pressure a scalar quantity when we know that pressure is force per unit area and ... A: In order for a quantity to be a vector quantity there must be a unique direction for that quantity ... | |
| physics-waves | 5/24/2008 |
| Q: the waves from a radio station van reach a home receiver by two paths. one is a straightline path ... A: In order for the direct wave and the reflected wave to produce destructive interference at the ... | |
| Help! | 5/22/2008 |
| Q: How long will it take a rock dropped from 2.0 above the surface of Mars to reach the ground? A: Do you mean 2 METERS above the ground? If so this is like any other freefall problem except that the ... | |
| electromagnets | 5/20/2008 |
| Q: I am looking to build a pretty strong electromagnet. A: how do I go about it, B: how strong can an ... A: The strength of any electromagnet that you make will be determined by two factors: the design of the ... | |
| Electronics: Resistors | 5/20/2008 |
| Q: Kovalcin, I want the equivalent resistor of the following. Please tell me that with explanation. ... A: As I understand this circuit it is essentially: two 1 ohm resistors in parallel in series with an ... | |
| why should we spend time in the sun? | 5/15/2008 |
| Q: why should we spend time in the sun? A: The most important reason for spending time in the sun is probably the generation of vitamin D by ... | |
| hooke's law | 5/13/2008 |
| Q: A 5000 kg truck drives over a pothole in the road that causes the truck to push down on all four ... A: The required concept here is, as the problem states, energy conservation. In this case the change in ... | |
| force | 5/12/2008 |
| Q: helo sir i hav some doubt related to reaciton force. suppose i hold a chalk on my hand out ... A: Your problem here is the meaning of "reaction force". The reaction force to the stone's weight is ... | |
| Can we jump further from west to east? It is not so simple a qustion | 5/11/2008 |
| Q: We knew from our high school teachers that we may jump for the same distance whether we jump from ... A: Much [but not all] of what you say it true, but what you are ignoring is that this effect you are ... | |
| conservation of momentum | 5/10/2008 |
| Q: As most know if a rotating object (a skater for instance) maintains it's mass but decreases its ... A: For a rotating object, such as a spinning ice skater, the product of the "moment of inertia" and the ... | |
| tennis | 5/9/2008 |
| Q: do you have any info about what physics has to do with tennis ANSWER: Physics topics related to ... A: When you strike a tennis ball the path followed by the tennis ball as it moves through the air is ... | |
| tennis | 5/8/2008 |
| Q: do you have any info about what physics has to do with tennis A: Physics topics related to tennis: momentum conservation, impulse, Newton's 2nd Law, 2 dimensional ... | |
| frequency/current | 5/7/2008 |
| Q: A circular coil of diameter 8 cm and consisting of 1000 turns is rotated in a 0.2 Tesla magnetic ... A: When the normal to the plane of the coil is parallel to the magnetic field [in other words, when ... | |
| Orbits | 5/6/2008 |
| Q: In Newton's time, the distance between the earth and the moon was known to be about 60 times the ... A: The orbit of a satellite can be predicted from Newton's 2nd Law. For a satellite orbiting the earth ... | |
| intereference of electromagnetic waves | 5/6/2008 |
| Q: do em waves of same or different frequencies interfere with each other? if not then i would like to ... A: The answer to the question is that interference is a transient effect! What does that mean? It means ... | |
| Sound | 5/5/2008 |
| Q: A rifle is fired in a valley with parallel vertical walls. The echo from one wall is heard 2.0 s ... A: Since the echo from one wall was after 2 seconds, the distance to this first wall must be ... | |
| Electrostats | 5/4/2008 |
| Q: what is the difference between electrostatic potential and potential difference? A: Generally, "electrostatic potential" refers to the electrostatic potential at a point relative to ... | |
| The metre | 5/2/2008 |
| Q: I understand that the metre is defined as the length of the path travelled by light in a vacuum ... A: We sometimes have to live with legacy decisions! Sure, we could define the speed of light as you ... | |
| Oscillatory motion | 5/2/2008 |
| Q: A man is found dead hanging at abouth the 7th story level from a bungee chord tied at the top of the ... A: If the assumption here is that the jumper was expecting to commit suicide by colliding with the ... | |
| frequency/velocity or a Ion | 5/1/2008 |
| Q: An unknown ion is accelerated through a potential difference of 10,000 volts and then enters into a ... A: The effect of a uniform magnetic field will be to cause the charged particle to move in a circular ... | |
| Physics | 4/30/2008 |
| Q: How much tension must a rope withstand if it is used to accelerate a 960-kg car horizontally along a ... A: If the elevator is accelerating upward the cable must be able to BOTH support the weight of the ... | |
| Symmetrical arguments supporting validity of clock-paradox in SR | 4/30/2008 |
| Q: Suppose we have 2 identical, synchronized clocks (C1 and C2))accelerating away from each other, ... A: From what I understand about the Special Theory of Relativity, the problem here is that your thought ... | |
| egg vehicle | 4/29/2008 |
| Q: My physics class has been assigned a project where we must create a vehicle that will transport an ... A: Attach the end of the stretched spring to a string which is, in turn, wrapped around the axle of the ... | |
| Oscillatory motion | 4/28/2008 |
| Q: What would be the natural oscillation period of a 30 kg child on a swing whose seat is 3.2 m below ... A: A child sitting on a swing is, for all practical purposes, a simple pendulum. The period T of a ... | |
| physics | 4/27/2008 |
| Q: if a Coulumb of electrons is passing through a load, how does the resistance in the load affect the ... A: The resistance of a load is determined by the degree of interaction between the moving charges and ... | |
| Physics Q's | 4/27/2008 |
| Q: with? 1.) Give Neils Bohr's explanation for the existence of Hydrogen spectral lines? 2.) The speed ... A: 1. Bohr looked at orbiting electrons as being like planets orbiting the sun. This model did not ... | |
| mecanics | 4/26/2008 |
| Q: In which of the following unit acceleration expressed ? A: Acceleration is defined to be the rate of change of velocity and is calculated by dividing the ... | |
| projectile motion | 4/25/2008 |
| Q: Ive been having trouble with this question. Three shells are fired that will simultaneously land ... A: All 2 dimensional problems of this type can be solved in the same way: break the problem into 2 ... | |
| should we spend time in thesun? | 4/24/2008 |
| Q: could you please answer these questions beacsue im really stuck in my school work! Should we spend ... A: There are a number of points on both side! Con 1. Causes skin cancer! This become all too common ... | |
| bowling ball dropped on an egg experiment | 4/21/2008 |
| Q: How can I prepare a raw egg to survive having a bowling ball dropped on it? The egg has to be ... A: How about using spray can insulating foam [polyurethane - available at Home Depot]? It will harden ... | |
| unifrom motion | 4/20/2008 |
| Q: "Rotor" is a ride found in the amusement parks that consist of a hollow cylindrical room( about 8 ft ... A: This is a Newton's 2nd Law problem; the sum of the forces in the direction of the acceleration must ... | |
| physics | 4/19/2008 |
| Q: http://en.wikipedia.org/wiki/Image:Wheatstonebridge.svg Using the link provided for the diagram. ... A: Using the loop rule 3 times where I1 is the current through R1, I2 is the current through R2, Ib is ... | |
| Egg drop | 4/18/2008 |
| Q: James, i have a question regarding the physics of an egg drop. I am not sure about the 2nd law but I ... A: The third law just says that the force exerted on the egg by the ground when it strikes the ground ... | |
| Physics | 4/18/2008 |
| Q: What does a negative displacement mean? What does a negative velocity mean? A: The answer to both of these questions is arbitrary! You get to decide although in some cases we ... | |
| length vs. period | 4/17/2008 |
| Q: I did a lab in my classroom about the length of the pendulum affect its period. the length and the ... A: The problem here is that you need to square the period T^2 not the length if you want to straighten ... | |
| Water Pressure Loss Due to Pipe Size Reduction | 4/15/2008 |
| Q: Mr. Kovalcin, I'm a little rusty on my physics and I'm not sure how to puzzle this out and show a ... A: The answer here is quite simple! It was a terrible idea to change the 1.25" line to a 0.75" line. ... | |
| Potential/kinetic energy | 4/15/2008 |
| Q: We're learning about potential and kinetic energy in 3rd grade. I understand that an apple on a ... A: The problem here has to do with the reference point being used. It is frequently quite convenient to ... | |
| Potential/kinetic energy | 4/14/2008 |
| Q: We're learning about potential and kinetic energy in 3rd grade. I understand that an apple on a ... A: After the apple falls it has lost its potential energy and converted into another form. Just as the ... | |
| Energy | 4/14/2008 |
| Q: Kovalcin, I have been doing some reading on energy, and I have found an interesting point: If ... A: It is possible for two generators producing two identical sinusoidal signals that are EXACTLY 1/2 ... | |
| Physics | 4/4/2008 |
| Q: By what factor should the length of a simple pendulum be changed in order to triple the period of ... A: The period of a simple pendulum is given by: T=2*pi*sqrt[l/g] where T is the period of the pendulum, ... | |
| Waves | 4/4/2008 |
| Q: 1. The intensity of a sound source is 67 dB's when 4 meters from the source. What is the intensity ... A: 1. The intensity of a sound is inversely proportional to the distance from the sound source ... | |
| Physical S. | 4/2/2008 |
| Q: 10 grams of iron has a temperature of 190 Fahrenheit. 100 grams of water has a temperature of 60 ... A: Because of energy conservation, the heat energy gained by the water must be equal to the heat energy ... | |
| Sound and Electromagnetism | 4/1/2008 |
| Q: How does sound relate to electromagnetism, if at all? Would 20Hz of sound be in any way equivalent ... A: No relationship at all with the exception that both phenomena are waves. That said, they are very ... | |
| force | 3/31/2008 |
| Q: sir A rocket is moving with constant speed in space by burning fuel and ejecting out burnt gases ... A: The momentum of the rocket plus its fuel will be constant. If you eject fuel out the rear of the ... | |
| Rotational motion | 3/31/2008 |
| Q: What is the formula for calculating the acceleration and velocity of the rolling body down an ... A: The easiest way to determine the acceleration and corresponding velocities of an object rolling down ... | |
| electromagnetics and electrostatics | 3/30/2008 |
| Q: iv got a probelm i need help solving regarding the above subject,your help would be much ... A: The electrostatic force between two charges is given by: Fe=k*q1*q2/r^2 where k is the electrostatic ... | |
| Light's gravity and black hole mass | 3/30/2008 |
| Q: Two questions: [1] I've read that photons exert a (tiny) gravitational effect. (I don't refer here ... A: 1] According to Special Relativity mass and energy are just different aspects of the same thing ... | |
| Hall Probe Physics Question | 3/25/2008 |
| Q: A Hall probe is constructed from a semi-conducting material of thickness 0.4 millimeters. When 5 ... A: A Hall Effect probe works because an external magnetic field acts on the moving charged particles ... | |
| magnetic field question | 3/25/2008 |
| Q: 4. An electron is forced to undergo uniform circular motion with a radius of 5 cm and a period of ... A: The magnetic force acting on a moving charged particle is always directed perpendicularly to the ... | |
| Ice Crystals | 3/24/2008 |
| Q: This is mywhy is in the middle of ice, white ? (have you noticed ?) I guess the reason must be ... A: To make truly clear ice requires extreme pressure. Interestingly, it is this transparency under ... | |
| pleeeeaaaaaaaaaaaasssseeee help! | 3/24/2008 |
| Q: 20.Balance scales measure a mass of 90 kg for a person and an apparent mass of 3.7 kg when submerged ... A: The mass of water is approximately [approximately because this depends on temperature to a small ... | |
| physics heat/wavelengths | 3/23/2008 |
| Q: 1. All matter contains both positively and negatively charged particles. Why do most things have no ... A: 1. Since opposite charges attract, in most cases positives and negatives cancel out on average. ... | |
| question | 3/22/2008 |
| Q: can you answer this question : "A bus is moving downhill at a slope of 5 degree on a rainy day. At ... A: Virtually all kinematics problems can be solved in the same way! There are 6 variables relevant to ... | |
| Newton's laws | 3/20/2008 |
| Q: If one looks at the planet Venus through even a small telescope, one sees that sometimes it looks ... A: The only time that Venus will look full to us is when it is on the opposite side of the sun. Why? ... | |
| Acceleration | 3/19/2008 |
| Q: I am currently studying an undergraduate sports mechanics course in which we're still trying to ... A: Virtually all kinematics problems can be solved in the same way! There are 6 variables relevant to ... | |
| Newton's Law | 3/18/2008 |
| Q: Two friends push on a 2200 kg car. The car is initially at rest, but after pushing on it for about ... A: According to Newton's 2nd Law the sum of the forces acting on an object is equal to the product of ... | |
| addition to the plasma ball question | 3/18/2008 |
| Q: How is a plasma ball related to well-known plasma sources...like the plasma in the sun, in plasma ... A: A plasma ball consists of a low pressure gas [the type of gas determines the color of the glow], two ... | |
| Time - given acceleration and distance | 3/16/2008 |
| Q: I have been examining a text book example question for hours on end, and though the answer is given ... A: Believe it or not ALL kinematics problems can be solved in exactly the same way! There are only 6 ... | |
| Physics Q's | 3/14/2008 |
| Q: help. 1.) A car traveling 20 mph can stop in about 40 ft. If the same car travels twice as fast, ... A: 1. If the car travels twice as fast it will contain 4x as much kinetic energy [KE=1/2*m*v^2] and so ... | |
| Fluid mechanics | 3/13/2008 |
| Q: I'm confused about some concepts about fluid motion. Putting a nozzle on a hose will increase its ... A: There are two relevant issues here, both of which you have hinted at. First, the law of continuity ... | |
| Syphons | 3/13/2008 |
| Q: Can you tell me please: In a syphon setup, why does the opening of the outlet pipe HAVE to be lower ... A: Actually, the weight of the liquid on the output side must be LESS than the weight of the liquid on ... | |
| Simple Harmonic Motion | 3/12/2008 |
| Q: How do you prove shock absorbers (springs) is SHM A: I am not quite sure what you mean by "prove" in this context. It is true that the suspension system ... | |
| physics | 3/10/2008 |
| Q: 33. A 500 kg car is traveling at 20 m/s. It applies the brakes doing to dodge a squirrel doing ... A: The easiest way to solve this problem is to use energy conservation. The initial energy of the car ... | |
| Lightning | 3/9/2008 |
| Q: Is there any instrument for measuring the temperature of lightning? if so what is the material used ... A: I don't know if such a device actually exists, but in principle such a device is quite ... | |
| Heat | 3/7/2008 |
| Q: A 3 kg rock is initially at rest at the top of a cliff. Assuming that the rock falls into the sea at ... A: Using energy conservation, the gravitational potential energy of this falling rock will be equal to ... | |
| Heat | 3/7/2008 |
| Q: A hot-water heater is operated by solar power. If the solar collector has an area of 6 m^2 and the ... A: Just look at the units! Dividing 550J by 3300J/s becomes J/[J/s] = J*s/J = s Seconds, the unit for ... | |
| Heat | 3/5/2008 |
| Q: A hot-water heater is operated by solar power. If the solar collector has an area of 6 m^2 and the ... A: The heat needed to raise the temperature of one cubic meter of water from 21oC to 61oC is given by Q ... | |
| Momentum and Collisions | 3/5/2008 |
| Q: An 85 Kg astronaut is working on the engines of a spaceship that is drifting through space with a ... A: Using momentum conservation, the momentum of the wrench will be equal to the momentum of the ... | |
| temperature | 3/4/2008 |
| Q: An average residential swimming pool might contain 15,000 gal. About how much energy would it take ... A: The heat needed to raise the temperature is given by Q=m*c*DT where Q is the heat added, m is the ... | |
| physics and wheels | 3/3/2008 |
| Q: I am helping my 5th grader w/ a science fair project and am having trouble finding research that ... A: In the absence of some special consideration I do not believe that it should really matter very much ... | |
| Applying Newton's Laws of Motion | 3/2/2008 |
| Q: a 4000 kg truck is parked on a 15 degree slope. how big is the friction force on the truck? A: Since the truck is NOT accelerating this must be a Newton's 1st Law problem. All problems of this ... | |
| Newton scooter | 3/2/2008 |
| Q: I need to make a newton scooter only using newtons 3rd law that will carry a cup of water and move 2 ... A: That would be entirely up to you! Use your imagination? You could get one of those cheap battery ... | |
| Newton scooter | 3/1/2008 |
| Q: I need to make a newton scooter only using newtons 3rd law that will carry a cup of water and move 2 ... A: In order to make this a "Newton's 3rd Law" scooter you will have to throw or eject something ... | |
| statics | 2/28/2008 |
| Q: a rod of wheight 5 N and length 2M is supported by three chords A,B and C it in turn supports a ... A: I could be wrong, but based on the problem as stated I believe that there are too many variables and ... | |
| Physics | 2/26/2008 |
| Q: How can we relate Vectors with scalars eg:in the relation V = (integral of)E vector * ds Vector ... A: There are two different types of fields: scalar fields and vector fields. A field is an area of ... | |
| ac dynamo | 2/25/2008 |
| Q: sir how is steady emf obtained from a fluctuating emf in an ac dynamo? A: A feedback mechanism controls to output of the generator. This can be done in a number of different ... | |
| miscellanoues | 2/23/2008 |
| Q: sir i wanted to ask few questions thought it is not of your subject expertise but i think you would ... A: 1. A spring balance will typically not be sensitive enough to weigh such a valuable substance - more ... | |
| electric current | 2/22/2008 |
| Q: James, my question is that what are the the few points that differ emf from pd(potential difference) A: Potential difference is a measure of the difference in potential energy that a positive charge will ... | |
| electricity production | 2/21/2008 |
| Q: Give me a technique of production of electricity at no cost in detailed knowledge. A: There is just no way to produce electricity at no cost in any useful amount! If such a thing was ... | |
| general physics | 2/21/2008 |
| Q: A small ball rolls around a horizontal circle at height y inside a frictionless hemispherical bowl ... A: The ball in this problem is moving in a circular path and is, therefore, accelerating centripetally. ... | |
| physics -circular motion | 2/18/2008 |
| Q: A 1500. kg car takes a 50.0 m radius unbanked curve at 15.0 m/s. What is the size of the friction ... A: Since this car is accelerating [centripetally in this case] Newton's 2nd Law applies. The 1st step ... | |
| The Work-Energy Theorem and Kinetic Energy | 2/17/2008 |
| Q: An extreme skier, starting from rest, coasts down a mountain that makes an angle 25.0° with the ... A: The easiest way to solve this problem would be to use energy conservation. The skier starts at the ... | |
| What exactly are "flames"? | 2/16/2008 |
| Q: What exactly are "flames"? From what I've read about, it's where atoms are rearranging, with a net ... A: Energy release in the situations you have described is the result of a decrease in electrostatic ... | |
| blocking of magnetic field | 2/14/2008 |
| Q: "fello sir", Is there existance of plate of any material which can block the magnetic ... A: The only material I know of that can completely block the passage of a magnetic field is a ... | |
| Physics | 2/13/2008 |
| Q: 1. Why does an iron core increase the magnetic induction of a coil of wire? 2. Why is a generator ... A: 1. Microscopic "magnetic domains" within the iron core [like tiny little atomic level magnets] ... | |
| cathodes | 2/11/2008 |
| Q: okay, let me see if i understand a cathode correctly. a cathode is an electrode. the way that this ... A: A cathode is a negatively charged object that is a source of electron flow [typically through a gas ... | |
| space motion | 2/10/2008 |
| Q: An astrounat repairing a communications satellite in deep space floats at rest with respect to the ... A: Using momentum conservation! Assuming that the astronaut is 22m from the air lock, is facing away ... | |
| Physics projectile motion | 2/8/2008 |
| Q: In a test of a new missile defense system, a missile is fired on a trajectory that would directly ... A: This is a center of mass problem [which of necessity ignores innumerable real world effects] where ... | |
| MAGNATIC | 2/7/2008 |
| Q: SIR WHY A MAGNATIC ATTRECT A PIECE OF IRON? A: Ferro magnetic materials [such as iron, nickel, etc] have microscopic particles within them where ... | |
| mickelson morleys experiment | 2/6/2008 |
| Q: my question is about mickelson morleys experiment. i want to know if they find out from their ... A: It it true that for hundreds of year this topic was the center of much debate, but when Young ... | |
| Physics | 2/6/2008 |
| Q: 1. In what sense are all magnets electromagnets? 2. All atoms have moving electric charges. Why, ... A: 1. All magnetism is the result of moving charged particles, usually this means electrons. In a ... | |
| magnetic physics | 2/5/2008 |
| Q: At New York City, the earth's magnetic field has a vertical component of 5.2 10-5 T that points ... A: The magnetic force on a current carrying wire is given by Fm=I*LXB where X is the cross product of L ... | |
| physics | 2/3/2008 |
| Q: A 1kg ball is hung at the end of a rod 1m long. The system balances at a point on the rod 0.25m ... A: The center of mass of any system can be found by multiplying the mass of each piece of the system by ... | |
| kinematic equations | 2/2/2008 |
| Q: i wanted to know how the kinematic equations were derived. Vf = Vi + at Vf^2 = Vi^2 + ... A: In my classes students develop these equations in the laboratory. What my students do is take a ... | |
| Angular motion | 2/1/2008 |
| Q: when you make a flip turn in the water, how can you calculated the angular acceleration of the ... A: Angular acceleration will be equal to the change in angular velocity divided by the time required ... | |
| Drag Force | 1/31/2008 |
| Q: I know that the drag forces in water are complicated. I found this equation about buoyancy force and ... A: I wouldn't think so. That doesn't make any sense to me. Forces are vector quantities and direction ... | |
| Physics problem | 1/30/2008 |
| Q: A balloon is rising vertically upward with a velocity of 5.6 m/sec releases as an object from the ... A: All kinematics problems of this type can be solved in the exact same way. First, identify each of ... | |
| physic of swimming | 1/30/2008 |
| Q: i have read your answer about the basic physic of swimming.i know those are basic stuff of physic.I ... A: Whether or not something floats is based on Newton's 1st Law; if a system is at equilibrium opposite ... | |
| Physics | 1/29/2008 |
| Q: 1. One example of a water system is a garden hose that waters a garden. Another is the cooling ... A: 1. An electric circuit is more analogous to the cooling system in a car. The same electrons cycle ... | |
| help!!! | 1/28/2008 |
| Q: A rock is tied to the end of a 35cm long string and whirled around in a circlee that describesa ... A: This is a Newton's 2nd Law problem - all of which are solved in the same way! 1) The first step in ... | |
| Bouyancy | 1/26/2008 |
| Q: I am trying to build a floatation device and need to know how many cubic inches of air does it take ... A: 100 pounds of water has a mass of 100lb/2.2pounds/kg=45.4kg. 1kg of water occupies a volume of 1 ... | |
| Electricity | 1/26/2008 |
| Q: I do not have 220 coming into my house. However, I do have 110 from each hot feed to my house going ... A: You must have measured incorrectly. One hot line will be +110 Volts above ground while the other hot ... | |
| Physics | 1/21/2008 |
| Q: Consider these two scenarios: A) A non-operating helicopter is placed on a pedestal which is 10 ... A: The fundamental difference here is that in the 2nd case your helicopter IS doing work! In order for ... | |
| Hydraulics Homework | 1/20/2008 |
| Q: There is a pump that has a force of 10N the Area of the pump is 1cm2 (First area). The pressure is ... A: I agree with your answer! This is a Newton's 1st Law problem - in which case opposite forces [in ... | |
| force | 1/20/2008 |
| Q: sir sir i hav one doubt in force 1) when ever force is applied on a body it accelerates. If a body ... A: The velocity of an object will remain constant if the the UNBALANCED force acting on the object is ... | |
| science | 1/19/2008 |
| Q: I am in the 8th grade and have to do a science project. I have to do a project on physical science. ... A: Why not make a "Rube Goldberg" machine? [Think about the game "Mousetrap"]. Rube Goldberg was a ... | |
| Compass Needle Polarity | 1/17/2008 |
| Q: In Gr. 10 Science we have been studying magnetism recently, and the following question has been ... A: The confusing point here is that the "North Pole" of the Earth is actually the "South Pole" of a ... | |
| Sonic boom | 1/17/2008 |
| Q: I have seen videos of Jet aircrafts leaving sonic boom when they cross the sound barrier. i.e., when ... A: Actually, the sonic boom is NOT a result of the jet crossing the sound barrier. Any object MOVING ... | |
| Physics | 1/16/2008 |
| Q: 1. Why do you not hear the sound of distant fireworks until after you see them? 2. Why would it be ... A: 1. Light travels MUCH faster [186,000 miles per second] than sound [346 meters per second]. 2. Sound ... | |
| Physics | 1/16/2008 |
| Q: How is Orbit achieved? A: Any rocket sitting on the surface of the Earth has insufficient energy to orbit the Earth. To do so ... | |
| Hamster powered night light | 1/15/2008 |
| Q: I am doing a science project on making a hamster powered night light, and I am in 8th grade. We are ... A: May I suggest that you attach a small DC motor [available at radio shack] to the rotating shaft of ... | |
| Physics Question | 1/15/2008 |
| Q: there is a hot air ballon whos forces at 5,120N upward, 4,050N downward, 1,520N left, and 950N. ... A: Add these 4 forces together and make their sum equal to the mass of the balloon times the rate of ... | |
| Naked Egg Drop Expeirement | 1/14/2008 |
| Q: i am creating an egg drop, only instead of protecting the egg when its dropped i have to drop an ... A: You want to makes your structure so that it slowly collapses as the egg collides. You want it ... | |
| Sound waves & Electronics | 1/13/2008 |
| Q: if I have a specific sound wave how am I able to reproduce that sound using electronic components ... A: There are specific ic chips designed to reproduce sound and there are many sites where amateurs ... | |
| force | 1/12/2008 |
| Q: sir i hav some questions regarding force Now i have learnt that force always cause acceleration or ... A: You are confusing the application of a single force with the application of several. In order for a ... | |
| electric force | 1/8/2008 |
| Q: 1.The force of repulsion that two like charges exert on each other is 3.8 N. What will the force be ... A: The equation relating the electrostatic force between charged particles is given by: Fe=k*q1*q2/r^2 ... | |
| optics | 1/7/2008 |
| Q: sir can you explain me why does sun appear oval and bigger in size during sun set and sun rise. I ... A: The light leaving the sun has to travel through the atmosphere to reach your eyes. When you look at ... | |
| standing waves | 1/6/2008 |
| Q: Concerning standing waves on a fixed length of string with a set frequency. By adjusting the tension ... A: Between the two adjacent resonances there are waves visible on the string, but there is no ... | |
| physics | 1/5/2008 |
| Q: how is physics involved in swimming ? Do you know where i can get more information on this subject ? A: Physics items involved in swimming! 1. Newton's 1st Law - Buoyancy - You float because the buoyant ... | |
| please help | 1/4/2008 |
| Q: I would greatly appreciate any help you may provide to me regarding the following question. I have ... A: 1. Your first solution is just fine - I get 31.9m. 2. For the second problem I get 329m, which may ... | |
| protons in the universe ... sort of | 1/3/2008 |
| Q: well sorry this is a tad long-winded - but basically i'm questionning some figures which i've ... A: Tough question, but let me try it this way. Assume: The number of protons per gram of matter = ... | |
| please help | 1/3/2008 |
| Q: I would greatly appreciate any help you may provide to me regarding the following question. I have ... A: The first part of this problems requires the use of momentum conservation. The initial momentum of ... | |
| physics project | 1/2/2008 |
| Q: I can't remember the name of this, and I've found that it's very hard to explain and look up. I ... A: You are talking about a "Rube Goldberg" machine. If you do a google search you will find MANY hits. ... | |
| water pressure | 12/31/2007 |
| Q: If a pressure sensor is placed underwater at a given depth, say… ten feet, and a twenty foot wave ... A: At any depth beyond the "wave base" the effects of wave amplitude should be unfelt. Wave base is the ... | |
| Center of gravity | 12/30/2007 |
| Q: How to loacte center of gravity (CG) of buildings, heavy machines? Is there any practical way to ... A: To find the 3 dimensional center of a machine perform 3 separate calculations: x [front to back], y ... | |
| Is neutron-neutron fusion easier to facilitate than proton-proton fusion? | 12/27/2007 |
| Q: Neutron-neutron fusion is an example of nuclear fusion because neutrons are nucleons. Is it possible ... A: Being easier isn't the only or even primary question. What is really important is whether or not the ... | |
| Basic a/c current question | 12/25/2007 |
| Q: I understand a 3 poles a/c outlet ( Northamerican standard ) has one outlet for the ground ( this is ... A: First of all, in AC electricity the voltage is NOT constant. In fact, the voltage of a 120 Volt AC ... | |
| relative motion | 12/23/2007 |
| Q: when i hear or come across this term relative motion i really don't understand fully what it means. ... A: In freefall up it traditionally taken to be positive. When the ball was released in the elevator its ... | |
| sub atomic particles | 12/23/2007 |
| Q: will sub atomic particles actions change because they are being watched vs. not being watched A: That is a tough question! Quantum theory does, in fact, imply that the mere act of observing an ... | |
| physis | 12/20/2007 |
| Q: i dnt understand the altwood machine and forces...can u help? A: The Atwood's Machine is a device consisting of a singly pulley attached to a fixed support, a string ... | |
| calorimetry | 12/19/2007 |
| Q: A hot, just-minted coper coin is placed in 101 g of water to cool. The water temperature changes ... A: When the coin is added to the water, the heat lost by the copper coin must be exactly equal to the ... | |
| Vectors | 12/11/2007 |
| Q: I am trying to study for my physics exam coming up, and I have seemed to have forgotten everything i ... A: The problem is that your time is incorrect! When you solved the displacement equation for the time ... | |
| Sound | 12/11/2007 |
| Q: If energy can never be created or lost, just transformed from one state to another; can you get a ... A: Technically what you say is true! If a collision between two objects occurs on the earth, some of ... | |
| EMP | 12/7/2007 |
| Q: Is there anything that is not nuclear, or otherwise harmful that can give off an electromagnetic ... A: "Never Say Never!" I think that such a hand held device is very unlikely! The way that EMP works is ... | |
| EMP | 12/6/2007 |
| Q: Is there anything that is not nuclear, or otherwise harmful that can give off an electromagnetic ... A: The EMP is caused by the intensity of the explosion and is not specifically related to the fact that ... | |
| Newton's Cradle | 12/5/2007 |
| Q: When you place a finger in between the middle of the Newton's cradle, somehting strange happens. ... A: Your finger changes the system completely by introducing an external force into the system. Momentum ... | |
| Physics | 12/5/2007 |
| Q: Choose the one alternative that best completes the statement or answers the question. 1. A car ... A: 1. ALL of these! More force is needed if the car is going faster. More force is needed to stop the ... | |
| Problem Sheet | 11/29/2007 |
| Q: I have got few problems and looking for answers to them. Can you please help me in this regard. ... A: 1. Moving your arms forwards will cause your torso to move in the opposite direction, hopefully ... | |
| Centripetal Force | 11/29/2007 |
| Q: I've been stuck with this problem for a long time. Can you help me? A 1100 kg car negotiates a ... A: First of all, the coefficient of kinetic friction is ONLY relevant if one surface is "sliding" past ... | |
| radioactivity | 11/28/2007 |
| Q: What is "radioactive equilibrium" And also, during beta plus decay, how is energy used to turn a ... A: Radioactive equilibrium occurs when a radionuclide is being generated as quickly as it is decaying. ... | |
| Magnetism | 11/25/2007 |
| Q: Would it be possible to create a solid state (no moving parts) electricity generator with a ... A: The ONLY way to generate an electric current from a magnetic field is to have a changing magnetic ... | |
| fluids | 11/21/2007 |
| Q: The cross-sectional area of the faucet is 1.8x10^-4m^2, and the speed of the water is 0.85 m/s as ... A: According to the "law of continuity" the product of the fluid flow rate and the cross section area ... | |
| My physics research paper on projectile motion | 11/19/2007 |
| Q: how does air resistance tie into projectile motions with initial velocity, gravity A: This is an incredibly complex question! Gravity isn't an issue, but speed, shape, surface texture, ... | |
| Why are magnetic field lines always depicted as pointing from north to south? | 11/18/2007 |
| Q: Southern magnetic energy is emitted from the side of a magnet taking in the lines of force. Northern ... A: First of all, the magnetic field is a defined quantity. A magnetic field is an area of space where a ... | |
| DIFFRACTION of Light | 11/17/2007 |
| Q: For diffraction of light through a single slit, Width of secondary maximum fringes = (Distance of ... A: 1. I don't think that the initial statement is correct. The equation predicting the location of the ... | |
| physics | 11/16/2007 |
| Q: I read that if you lift a backpack you are doing work..but once on your back and when you walk no ... A: I don't agree with the second part. Walking the backpack forward does indeed require work. Now it ... | |
| ,electricity, | 11/14/2007 |
| Q: sir if a point charge is realesed in a non uniform electric field with field lines in same direction ... A: If the electric field is uniform [meaning that the electric field lines are parallel and equally ... | |
| nuclear physics,equilibrium | 11/13/2007 |
| Q: sir can you please tyell me the pracctical application of special theory of relativity? also tell if ... A: Incredibly, the Special Theory or Relativity has led to or can explain many different phenomena! 1. ... | |
| Physics B - Centripetal Force Question #2 | 11/12/2007 |
| Q: I'm having a hard time with this question. ... A: First of all, your force diagram is essentially correct. What you need to recognize is that the ... | |
| Fluids | 11/12/2007 |
| Q: Two identical containers are open at the top and are connected at the bottom via a tube of ... A: To make this problem easier, let's assume that the density of mercury is 13 times the density of ... | |
| Physics B - Centripetal Force Question | 11/11/2007 |
| Q: I'm having some trouble understanding centripetal force. I know that the force is always towards the ... A: Let me begin by explaining centripetal acceleration in an entirely different way. Acceleration is ... | |
| Spring | 11/10/2007 |
| Q: A spring, with a spring constant of 50 N/m is initially compressed by 3cm. How much work is required ... A: Your are, of course, interested in the positive answer since you are looking for the additional work ... | |
| Spring | 11/9/2007 |
| Q: A spring, with a spring constant of 50 N/m is initially compressed by 3cm. How much work is required ... A: The energy stored in a spring is given be U=1/2*k*Dx^2 where U is the energy, k is the spring ... | |
| rotation of earth | 11/8/2007 |
| Q: why do storms or high speed winds move forward spirally? A: Sorry, I accidentally hit reject. Here is my answer! According to Newton's 1st Law, "An object in ... | |
| physics | 11/8/2007 |
| Q: 1.Introduction One important elementary example of motion is that of free fall, which is the ... A: 1. This first question can be answered by using the data given above to plot a graph of Displacement ... | |
| physics | 11/7/2007 |
| Q: I can lift a bag off the floor,a weightlifter can lift more than his body weight.Why can he not lift ... A: The difference is that in the case of the cage there is an EXTERNAL force being exerted on the ... | |
| Quantum physics/mechanics vs old school mechanistic physics | 11/6/2007 |
| Q: I'm doing some research for a speculative fiction novel based around the 19th century concept of the ... A: The problem with this sort of speculation is the you have stated an "if ... then" statement where ... | |
| Boiling water | 11/3/2007 |
| Q: What affect does elevation have on waters bioling point and would the type material a pot is made of ... A: Water [or any other liquid for that matter] boils when the vapor pressure of the liquid exceeds the ... | |
| Bike riding and wind resistance | 11/2/2007 |
| Q: I have a question. If I ride 15 mph in an upright position (about a 12 o'clock position), how much ... A: I don't really know the magnitudes for the forces involved because they depend on so many different ... | |
| physics | 11/1/2007 |
| Q: A 250 gram baseball traveling with a velocity of 40m/s is hit by a bat and leaves at 60 m/s in the ... A: To solve this problem make use of the "Impulse" equation: F*Dt=m*Dv where F is force, Dt is the time ... | |
| kinetic friction | 10/31/2007 |
| Q: A car is turning on a curve whose radius of curvature is 23.1 meters. If the car is traveling a 13 ... A: This problem is fundamentally a Newton's second Law problem where the sum of the forces acting on an ... | |
| centipetal force at the TOP of a string | 10/29/2007 |
| Q: A girl swings a ball in a vertical circle at the end of a string. Is the force applied by the ... A: The only difference in the roller coaster problem is that the force causing the coaster to move in a ... | |
| AP Physics B | 10/28/2007 |
| Q: 1. A push broom of mass m is pushed across a rough horizontal floor by a force of magnitude T ... A: 1. First make a force diagram. In this case: Force Normal - up, Force of Gravity - down, Force of ... | |
| Optical Fibres | 10/27/2007 |
| Q: My question is about the time it takes for: a) a ray of light travelling down the central axis of a ... A: Given that the critical angle is 71.5degrees. Form a right triangle where one angle is 71.5 degrees, ... | |
| 1st law of thermodynamics | 10/27/2007 |
| Q: I have been doing some mind games inspired by teaching basic physics to the kids.. and have a ... A: Actually, the energy has NOT been lost! The total energy released through E=mc^2 at sea level would ... | |
| earth science | 10/25/2007 |
| Q: what are the physics of an egg drop project such as pertaining to gravity an kinetic energy in those ... A: When an egg [or any other object for that matter] is dropped from a height h, the egge begins with ... | |
| Newton's 3rd Law | 10/25/2007 |
| Q: A squirrel with an arm full of nuts is sliding across an icy flat roof close to the edge. He ... A: The squirrel throws the nuts off the roof. Because of the 3rd Law every action is accompanied by a ... | |
| testing electromagnets in liquids | 10/24/2007 |
| Q: I am doing a science project on electromagnets and my teacher wants me to test the electromagnet in ... A: In my opinion, most of these liquids would have very little effect on the magnetic field. Why? ... | |
| voltage | 10/20/2007 |
| Q: I would like to buy a small, brush motor with no more than 1.5 volts present at the electrodes. ... A: The "nominal voltage" is the voltage across the motor while under normal operating conditions. The ... | |
| Circuits | 10/17/2007 |
| Q: I don't understand how diameter affects current. Very confused! Please help, here is theA ... A: Think of the wire as if it were a pipe. If you double the diameter of a pipe you will quadruple the ... | |
| physics | 10/17/2007 |
| Q: Flywheels are large, massive wheels used to store energy. They can be spun up slowly, then the ... A: The key to solving rotational problems is to pretend that the problem is linear, but replace each of ... | |
| Physics | 10/16/2007 |
| Q: What is elastic potential energy? Show one sample calculation of the elastic potential energy ... A: Elastic potential energy is a measure of a system' ability to perform work [apply a force through a ... | |
| Projectile Motion | 10/15/2007 |
| Q: A shell is fired from the ground with an initial speed of 1.70*10^3 m/s at an initial angle of 55 ... A: I really just answered a similar question which I have posted below. Subject: Projectile motionA ... | |
| physics-acceleration equations | 10/1 |