| Subject | Date Asked |
|
| the "why exactly so?" for the nature of the gravitational force | 11/19/2009 |
Q: I want to find the answer about the nature of the gravitational force.For which exact reason do 2 ...
A: Nobody knows the mechanism. It's just a fundamental property of mass that there's an attractive ...
|
| Energy and Expanding Universe | 11/13/2009 |
Q: If energy cannot be created or destroyed in the universe, then what does it mean that the universe ...
A: The law used to state that energy cannot be created or destroyed but can be changed in form. That's ...
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| Energy and Expanding Universe | 11/13/2009 |
Q: If energy cannot be created or destroyed in the universe, then what does it mean that the universe ...
A: It's not true that energy cannot be created or destroyed. That changed when fission was discovered ...
|
| What is magnetic force | 11/8/2009 |
Q: During academic years, we have been taught that a magnet emits lines of force. I'm not not clear ...
A: It's hard to describe what you can't see. You just have to visualize them. There is a magnetic ...
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| Trigonometry | 11/5/2009 |
Q: I need help with these mister. (NOTICE ABOUT THESE QUESTIONS) Show enough of your work to indicate ...
A: 1. 1/2 = 1-2(1/4) = 1/2 2. a. 12(1/2)-(6/2)(2^1/2) +(2^1/2)/52 = b. (3^1/2)/2 +1 -(3^1/2)/2 +2^1/2 ...
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| What is magnetic force | 11/5/2009 |
Q: During academic years, we have been taught that a magnet emits lines of force. I'm not not clear ...
A: There are field lines surrounding a magnet but they're not really lines of force. The only way to ...
|
| mechanical advantage | 10/30/2009 |
Q: how do i calculate the mechanical advantage of a simple screw jack?
A: It's the distance the end of the lever turns in one revolution divided by the pitch of the screw ...
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| Physics | 10/30/2009 |
Q: sketch the electric field lines for -2q and +q charges placed some distance apart.
A: I can't sketch it for you. Electric lines go out from a positive charge and terminate at a negative ...
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| physics | 10/29/2009 |
Q: Question 1: A 1.5-kg object moves up the y-axis at a constant speed. When it reaches the origin, the ...
A: 1. the sum of those forces is -0.975 in the y-direction and 8.975 in the x-direction. (a) no (b) ...
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| physics | 10/27/2009 |
Q: Car A hits car B (initially at rest and of equal mass) from behind while going 36 m/s. Immediately ...
A: KE before = (1/2)m(36)^2 = 648m KE after = (1/2)m(27)^2 = 364.5m fraction lost = ...
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| physics | 10/27/2009 |
Q: A girl of mass m1 = 60 kilograms springs from a trampoline with an initial upward velocity of v ...
A: Initially, KE = (1/2)mv^2 = 1920J After 2 meters, PE gained = mgh = 1176J So KE remaining = 744J = ...
|
| infinity in both directions | 10/19/2009 |
Q: Thinking about infinity radiating outwards from our personal observation point (our eyes and/or our ...
A: Sure, there are a lot of small things. That's why they invented microscopes. However, there are ...
|
| Rotation physics | 10/19/2009 |
Q: A golfer starts with the club over her head and swings it to reach a maximum speed as it contacts ...
A: There are two acc. vectors. The acc. vector due to the velocity of the club is going to point ...
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| Physics Questions | 10/14/2009 |
Q: "This isn't an assignment. It was a project. My teacher said we can find answers using the net. 1. ...
A: Some of these are not physics. I'll answer what I can. 2. the lady with spike heels. pressure = ...
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| Physical Science (Mechanics) | 10/11/2009 |
Q: A stone falls from a ledge and takes 16 seconds to hit the ground. The stone has an original ...
A: Well, since you should have learned that KE = (1/2)mv^2 = (1/2)(20)(2.8^2) = 78.4J, tell me where I ...
|
| Physical Science (Mechanics) | 10/11/2009 |
Q: A stone falls from a ledge and takes 16 seconds to hit the ground. The stone has an original ...
A: Well, of course I fully understand these questions. I have taught physics and have solved physics ...
|
| Uniform circular motion | 10/7/2009 |
Q: How does uniform circular motion work? My understanding is that if a car is in an upwards rounded ...
A: The car has to follow the curve of the road so it goes in a circular motion. Acceleration means a ...
|
| change in metal compounds. | 10/7/2009 |
Q: i would like to ask you a brief but specific question about the reactions of metal compounds. by ...
A: As you know, uranium has 92 protons and 92 electrons. In addition, U-238 has 146 neutrons in the ...
|
| "Electric Fog" | 10/4/2009 |
Q: This may sound odd, but I would like a serious answer or I wouldn't bother to ask so... My Ideas on ...
A: I can't say that some of those phenomena are not related but I can say that they're not due to very ...
|
| physics problem | 10/4/2009 |
Q: I'm a junior in highschool taking physics http://www.webassign.net//student.pl?x=6924271253 ...
A: Since distance = velocity times time, you need to find the area under the curve for the two time ...
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| electric potential | 10/2/2009 |
Q: A parallel plate capacitor is composed of two square plates, 10.0 cm on a side, separated by an air ...
A: C = epislon(A/d) = 1.11x10^-10F Q = CV = 16nC If you double the gap the charge drops to 8nC Energy ...
|
| Stress and strain | 9/9/2009 |
Q: Can you explain what they are in detail and why when 2 thing when hit with the same force even if ...
A: Stress is defined as force per unit area, F/A. Strain is what results when a certain stress is ...
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| physics | 9/8/2009 |
Q: Calculate the magnitude and direction of the Coulomb force on each of the three charges shown in the ...
A: The 6uc charge experiences a force to the left due to the 1.5uc charge and a smaller force to the ...
|
| HELP PLEASE | 9/7/2009 |
Q: Suppose a 1.0 g nugget of pure gold has zero net charge. What would be its net charge after it has ...
A: 1g of gold has (1/196.97)(6x10^23) = 3.05x10^21 atoms Since each atom has 79 electrons, that's ...
|
| physics | 9/7/2009 |
Q: Two small metal spheres are 25.0 cm apart. The spheres have equal amounts of negative charge and ...
A: 1. 0.034 = (9x10^9)q^2/(0.25)^2 so q = 4.85x10^-7 C 2. F = qE = (-6.1x10^-7)(1.1x10^6) = -0.67N ...
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| physics | 9/5/2009 |
Q: Three charges are arranged as shown in the picture above. Find the magnitude and direction of the ...
A: F(3) = 9x10^9(3x10^-9)(6x10^-9)/(0.707)^2 = 8.1x10^-8N/C F(2) = 5.4x10^-8N/C F(x) = 8.1x10^-8cos(45) ...
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| physics | 9/4/2009 |
Q: Case Study: The Case of A Handsome Professor To practice his demonstration of the Law od ...
A: Without the naughty student, the pendulum would swing back and nearly touch the professor's nose. ...
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| physics | 9/3/2009 |
Q: Calculate the magnitude and direction of the Coulomb force on each of the three charges shown in the ...
A: F = kq1q2/r^2 1) F = k(6x10^-6)(1.5x10^-6)/(0.03)^2 -k(6x10^-6)(2x10^-6)/(0.05)^2 = 75-43.2 = 31.8N ...
|
| Electricity | 9/1/2009 |
Q: when you connect two cells in parallel in a circuit,what is the direction of current ,i mean the ...
A: If you simply connected the cells to each other, then what you are saying is true and one battery, ...
|
| mass or no mass | 8/28/2009 |
Q: Richard, are there particles that contain no mass (by that I mean, is this theory or actually ...
A: Photons do not have mass. They are little packets of energy. You have to realize that when we say ...
|
| microwave damage to water | 8/25/2009 |
Q: I have been told by my friends who are health food believers that you should not use a microwave ...
A: If it removed all the nutrients where did they go? Microwave energy is only absorbed by water ...
|
| Young's Modulus of Elasticity related problem | 8/23/2009 |
Q: A 14.5 kg mass, fastened to the end of a steel wire of unstretched length 1m, is whirled in a ...
A: Young's Modulus is defined as (F/A)/(dL/L) where F is the force, A the cross sectional area, dL the ...
|
| light wavelengths | 8/15/2009 |
Q: I do not understand very much about light or its properties. I was reading about constructive and ...
A: When we talk about a red shift from distance stars, the light appears to be shifted because of the ...
|
| light wavelengths | 8/15/2009 |
Q: I do not understand very much about light or its properties. I was reading about constructive and ...
A: Yes, you can mix blue light with yellow light to get a new color. Yes, you can shift wavelengths ...
|
| atom | 8/11/2009 |
Q: Is gravitational force an electromagnetic force? How this gravitational force get created from an ...
A: A gravitational force is entirely different from an electromagnetic force. Any two objects that ...
|
| light | 8/11/2009 |
Q: What is real and virtual image? And tell me about diffraction, interference and polarisation please.
A: Real and virtual images are formed by lenses and mirrors. A real image can actually be formed on a ...
|
| light | 8/1/2009 |
Q: I've finished my 12th standard. How a rainbow appears in a rain? Is it due to colloidal particles? ...
A: You can only see a rainbow after the rain has passed and the sun is at your back at a certain angle. ...
|
| electric current | 8/1/2009 |
Q: what is the difference b/w E.M.F and terminal potential difference
A: An emf is simply a source of energy to keep a current flowing in a circuit. It could be a battery, ...
|
| Speed of Light and Time Space | 7/31/2009 |
Q: Einstein's major insight, which led him to the Theory of Relativity, was the realization that the ...
A: You're getting too philosophical for me. The way I consider it, if time ran backwards, then entropy ...
|
| Speed of Light and Time Space | 7/31/2009 |
Q: Einstein's major insight, which led him to the Theory of Relativity, was the realization that the ...
A: Wow, that's the first time I've ever seen a picture of the person sending me a question. Time is a ...
|
| Physics Problem Solving | 7/25/2009 |
Q: 1. A 0.40 kg iron horseshoe that is initially at 500 degrees Celsius is dropped into a bucket ...
A: In all of these, heat lost = heat gained 1. 0.40(470)(500-t) = 20(4186)(t-22) so t = 23.07 degrees ...
|
| Acceleration in space | 7/24/2009 |
Q: A golf ball struck by a club on earth is the maximum speed just off the head of the club or does ...
A: As soon as the ball leaves the head of the club it accelerates due to gravity. That acceleration is ...
|
| atom | 7/15/2009 |
Q: I've finished 12th grade. How the nuclear force get created in the nucleus? How this powerful force ...
A: Scientists are still trying to figure out the force holding the nucleus together. Gravity is what ...
|
| Gravity | 7/15/2009 |
Q: I've finished my 12th standard. Our earth behaves like a magnet. Earth can have gravitational field ...
A: The Earth has a magnetic field because of its liquid iron core. If you have a spherical magnet or ...
|
| physics | 7/14/2009 |
Q: .... following is a question in my physics book... The moon is observed from two diametrically ...
A: Draw an isoceles triangle with the Earth at the base and the moon at the top. Now draw a line ...
|
| Alternating current | 7/13/2009 |
Q: explain how the use of transformers improves the efficiency of power transmission. Many thanks
A: As current passes through a wire it produces heat according to the relationship I^2R. So the lower ...
|
| The Honey Dilema??? | 7/10/2009 |
Q: I was taking some honey from a jar of set Honey and the strangest question entered my mind! If you ...
A: It's not the viscosity that would keep you on the surface of the honey, it's the density. You're ...
|
| Regarding the Discharging of a Capacitor! | 7/9/2009 |
Q: Raridon, I'm having trouble with the following question...It's asked in the analysis part of a lab ...
A: 1. So you start with 1000 at time 0. After one hour you take out 10% so you have 900 remaining. ...
|
| Regarding Components, Direction, and Magnitude of point charges! | 7/8/2009 |
Q: Raridon, 1.) Find the x and y components and the magnitude and direction of the electric field at ...
A: I presume you're still talking about the charges at -0.18m and +0.18m. So the distance from each of ...
|
| Battery and Leyden jar | 7/7/2009 |
Q: What's the difference between battery and Leyden jar?
A: the Leyden jar was an early device for storing static electricity by having conductors inside and ...
|
| Regarding electric fiels and point charge! | 7/7/2009 |
Q: Raridon, This is what's given: In a rectangular coordinate system, a positive point charge q ...
A: #2, if it's E at the origin, then that's 0. for your new problem, you need to put in the distance to ...
|
| Light | 7/5/2009 |
Q: Can you tell me what kind of light can't go through the water. For example, umbrellas can block UV. ...
A: You're not talking about visible light since UV is outside the visible range. Both are just part of ...
|
| physics | 7/4/2009 |
Q: The displacement of an oscillating mass is given by x(t) = 20 cos( 5 t ). 1)What is the initial ...
A: Do you understand that velocity is the rate of change of displacement and acceleration is the rate ...
|
| Electric Field Mapping Question! | 7/2/2009 |
Q: Raridon, I have a question regarding a Physics lab on Electric Field Mapping! The question is as ...
A: I presume you're sketching out electric field lines between parallel plates. In the central region ...
|
| capicetance | 6/30/2009 |
Q: we know that c= q/v if q=1c and v=1volt then c=1f this is very big ...
A: Obviously because 1C is a very large charge. If a 1 Farad capacitor had plates separated by 1mm, ...
|
| need help. | 6/29/2009 |
Q: 1)WHEN A BUCKET FULL OF WATER IS RAPIDLY WHIRLED IN A VERTICAL CIRCULAR PATH WATER DOESN'T FALL EVEN ...
A: 1) That's because there's a centripetal force due to the water moving in a circular path that ...
|
| electricity | 6/28/2009 |
Q: In electricity practicals when you turn up the voltage the current will increase. But when ...
A: Sure, if you have a constant resistance then increasing the voltage increases the current, V = IR. ...
|
| physics | 6/27/2009 |
Q: A 1100-kg rocket has a net propulsion force of 70 kN (kiloNewtons). Over a short time period, it ...
A: 1. 35m/s to 60m/s = 25m/s change, convert to mph 2. Impulse = Ft = 70000(0.393) 3. v = v0+at so 60 = ...
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| physics | 6/21/2009 |
Q: Block 1 (m1=1.5 kg) and block 2 (m2=1 kg) are on the surface of a table as shown in the figure. The ...
A: The normal force on m1 = 1.5(10)-5 = 10N The normal force on m2 = 1(10) = 10N Frictional force on ...
|
| should we spend time in the sun ?? | 6/17/2009 |
Q: well im doing a science exam in school at the moment and im woundering weather you can help me. im ...
A: A short time in the sun wearing sunscreen will help you produce Vitamin D. Spending extensive time ...
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| physics | 6/17/2009 |
Q: Forces F1 and F2 act on a mass m = 0.79 kg, as shown in the diagram below. The magnitudes of the ...
A: 1) F1x = 3cos(79) = 0.57N, F1y = 3sin(79) = 2.94N 2) F2x = 3.6cos(15) = 3.48N, F2y = 3.6sin(15) = ...
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| physics | 6/17/2009 |
Q: Forces F1 and F2 act on a mass m = 0.89 kg, as shown in the diagram below. The magnitudes of the ...
A: 1) F1x = 1.9cos(51) = 1.20N, F1y = 1.9sin(51) = 1.48N 2) F2x = 3.7cos(26) = 3.33N, F2y = 3.7sin(26) ...
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| physics | 6/16/2009 |
Q: A cannonball is fired from a gun with a muzzle velocity of 80 m/s at an angle of 65 degrees above ...
A: The vertical component of the velocity would be 80sin(65) = 72.5m/s 1) v = gt so 72.5 = 9.8t and t = ...
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| About gravitational potential energy | 6/13/2009 |
Q: I have a question regarding the formula g=GM/r^2: In my lecture notes, it says "For a spherical ...
A: As you probably know, every bit of mass attracts every other bit of mass. The equation is F = ...
|
| Earth's Magnetic Field | 6/1/2009 |
Q: Have heard two things on the Earth's magnetice field that it is reversing and/or will decline to ...
A: The Earth has been going for about 4.5 billion years which is also approximately the half-life of ...
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| Electrical Potential | 5/31/2009 |
Q: Consider three identical metal spheres, A, B, and C. Sphere A carries a charge of -2.0 uC; sphere B ...
A: After A and B are touched and then separated they will each have a charge of -4 uC. After B and C ...
|
| Emission And emission Spectra | 5/31/2009 |
Q: Sir,,i am a new to atomic physics and have many queries in my mind.......i was recently studying ...
A: 1) Yes, the substance has to be vaporized to produce a line spectra. Consider neon signs. A ...
|
| gravitational pull | 5/31/2009 |
Q: i was just wondering about gravitational pull. Is it true that the sun pulls all planets in to their ...
A: The planets stay in their orbits around the sun because of balanced forces. The force of gravity ...
|
| Electric field | 5/31/2009 |
Q: What are the differences between electric and magnetic fields?Thanks
A: electric fields surround electric charges. electric field lines start at a positive charge and end ...
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| physics | 5/28/2009 |
Q: After repeated pleas, mention of liability issues and possible criminal prosecution for negligence, ...
A: Regardless of the mass, any body falling experiences 1 g. It's not the falling that hurts you, it's ...
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| Physics | 5/27/2009 |
Q: A common saying goes, "it's not the fall that hurts you; it's the sudden stop" Translate this into ...
A: That's Newton's second law, F = ma. The attraction between your body and the Earth is given by F = ...
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| in nuclear reactions | 5/27/2009 |
Q: Richard I'm somehow confused about liberated energy and total energy, I'd like to know the ...
A: I assume you're talking about radioactive atoms. They are unstable and want to go to a lower energy ...
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| Energy | 5/27/2009 |
Q: I am a business major from East Carolina University and have limited experience with physics. Still ...
A: Energy is created and destroyed all the time in nuclear reactions. We get our energy from the sun ...
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| fluid dynamics | 5/26/2009 |
Q: I am in high school 11th grade I never heard of fluid dynamics before i read about it in a web so i ...
A: Fluid dynamics obviously deals with fluids moving. That can be water, air , or another fluid. I ...
|
| Liberated energy nuclear reactions | 5/23/2009 |
Q: Richard where does liberated energy go to? and why it's liberated? and why do we have (M before- M ...
A: In certain atomic reactions, such as take place in our sun, the mass of the product is less than the ...
|
| nuclear physics | 5/18/2009 |
Q: sir I want to ask that what are the reasons that half life of a radioactive substance is smaller ...
A: The half-life is the time for one half of a given number of radioactive atoms to decay to a lower ...
|
| Magnetism/Induction | 5/17/2009 |
Q: Could you please clearly (and simply!) explain to me how an AC motor works? I am finding it ...
A: It's sort of like keeping the rabbit in front of the dogs at the race track. The armature rotates ...
|
| some problems involving rotational motion | 5/14/2009 |
Q: I got very confused at the physic lesson today, here are some problems I hope you can help me with. ...
A: 10 Since it's not skidding you have to use the static friction which gives you 26.5m/s 2) T+mg = ...
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| Work and Energy | 5/8/2009 |
Q: A ball on a roller coaster of mass 0.01 kg with zero non-coservative forces seems to conserve its ...
A: It looks like the first two sets fall within experimental error although I doubt that your accuracy ...
|
| levers? | 5/7/2009 |
Q: I am having an argument with a puzzle publisher....please look at this picture. ...
A: the editor is correct. you're dealing with moments, the product of force times distance which can ...
|
| production of electricity | 5/7/2009 |
Q: how does a generator produce electricity how does photovoltaic cells produce electricity what are ...
A: It would be better for you to go to www.wikipedia.com and put in "electrical generation" and ...
|
| Blacklights | 5/5/2009 |
Q: Do you happen to know if anyone sells a very bright blacklight? Unlike those $50 Spencer's gifts ...
A: By definition, a blacklight is not going to light up a room since ultraviolet is not visible light ...
|
| 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: mass has nothing to do with gravity. mass is a product of the volume of an object and its density. ...
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| why should we spend time in the sun | 4/27/2009 |
Q: what happens we when spend to much time in the sun and what does effects does it have on the earth ...
A: You don't get as much sun there as we do in the US. While some exposure to the sun may be ...
|
| energy | 4/24/2009 |
Q: Your help is very much appreciated. 1- A novice skier, starting from rest, slides down a ...
A: 1- Since it's frictionless, you only have to consider the height. mgh = (1/2)mv^2 so v = 49.5m/s 2- ...
|
| Light Interference | 4/14/2009 |
Q: Respected Sir, Do constructive and destructive light interference take place simultaneously? Is ...
A: Light consists of waves. Waves have maxima and minima. If the maxima of two different waves occur ...
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| Magnetic North, the amount of Iron | 4/6/2009 |
Q: I am doing a report and had a question in my mind about the amount of iron required to be removed ...
A: You can talk about a large usage of steel, but not infinite. If you removed all the iron from below ...
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| friction | 4/6/2009 |
Q: A 182 g block is launched by compressing a spring of constant k=200 N/m a distance of 15 cm. The ...
A: The energy stored in the spring is (1/2)kx^2 = 2.25J The frictional force = 0.27(.182)(9.8) = 0.482N ...
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| physics | 4/3/2009 |
Q: Two identical pucks are on an air table. Puck A has an initial velocity of 2.3 m/s in the positive ...
A: If two identical pucks collide elastically, the angle between them after the collision is 90 degrees ...
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| physics | 4/3/2009 |
Q: i have a problem i need help with. A 20 lb ladder that is 10 feet long leans against a smooth ...
A: The ladder extends 8 feet up the wall and the base is 6 feet from the wall. If you take the moments ...
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| Electricity | 4/2/2009 |
Q: Respected Sir, I am student of class 11, Which is greater drift velocity attained by an electron or ...
A: Thermal velocity is probably greater but that's random in all directions. Drift velocity is the ...
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| physics(electricity) | 4/2/2009 |
Q: please tell me the difference between resistance and resistivity in simple language.plz elaborate ...
A: resistivity is a property of a material, just like density. You will find tables of resistivity ...
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| magnetism | 3/28/2009 |
Q: I'm a fifth grader doing a report on magnets.Some of my questions are... What's inside a magnet that ...
A: Most magnets are made of iron, like what you find in a nail. They also use cobalt and nickel. It's ...
|
| moment of inertia | 3/26/2009 |
Q: what is the moment of inertia ?
A: inertia is a measure of how hard it is to move something. If you want to move something in a ...
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| Physics: Torque Question | 3/26/2009 |
Q: To Richard, Thank you so much for taking the time to read over my question regarding torque. This ...
A: A lever is a simple machine. The mechanical advantage is the ratio of the long segment of the board ...
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| Physics | 3/23/2009 |
Q: I was just wondering if you could help me get started on this5. An electron is travelling in the ...
A: The time for the electron to reach the plate is 3x10^-3/4x10^4 = 7.5x10^-8s. The acceleration to ...
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| physics | 3/22/2009 |
Q: Out of 8 coins you have with you, one is heavier while the remaining 7 coins have equal weights. By ...
A: Put 3 coins on each side of the scale. If they weigh the same then the heavier coin is one of the ...
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| electric field intensity | 3/20/2009 |
Q: sir the electric field intentsity E of an infinite plane charged sheet is (charge density)/2 * ...
A: E = kq/r^2 You have to sum this up over the entire sheet. For an infinite sheet you have a point in ...
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| ELECTRICAL | 3/19/2009 |
Q: you are observing the effect of a single ponit charge with a magnitude of +4.3( looks like ...
A: I presume you mean 4.3uC where the u has a little tail on it. That's the symbol for "micro" or ...
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| Physics Question | 3/18/2009 |
Q: Raridon I have a question that I can’t find its answer. The question is: A person pulls a box on ...
A: Your English is fine. Much better than my Iranian. I'm going to use u since I can't type mu, and ...
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| Draging an object | 3/16/2009 |
Q: I would like to know if you can guide me to find all the forms known to drag an object. If magnetism ...
A: Certainly you can drag an object using a magnet if the object contains iron, cobalt, nickel or a few ...
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| Physics | 3/15/2009 |
Q: I just need some explanation, please? Determine the electric field at the origin o in Fig. Due to ...
A: E = kq/r^2 = kQ/l^2 (a)E(A) is E straight down E(B) is 60 degrees west of south E(B) west is ...
|
| help plz | 3/13/2009 |
Q: Q1. A projectile is launched at an upward angle of 30˚ to the horizontal with a speed of 30m/s. ...
A: Q5. vcosA = 3/1.3 = 2.308m/s 0 = 5+[vsinA]t -(1/2)gt^2 so vsinA = 2.524m/s (a) so v = 3.42m/s at an ...
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| help plz | 3/13/2009 |
Q: Q1. A projectile is launched at an upward angle of 30˚ to the horizontal with a speed of 30m/s. ...
A: Q1. The horizontal component of the velocity is constant throughout the flight, 30cos(30). Q2. ...
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| Physics: Momentum? Help Please!!!! | 3/12/2009 |
Q: To Richard, Thank you so much for taking the time to read over my question regarding momentum. This ...
A: A. the car since it's smaller B. Probably not fair to ask me this since I taught physics and have ...
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| physics | 3/10/2009 |
Q: A 2.0 kg ball is thrown vertically from ground level into the air with an initial velocity of 10.0 ...
A: V = V0 -gt so 3 = 10 -9.8t and t = 0.714s H = v0t -(1/2)gt^2 = 10(0.714)-4.9(0.714)^2 = 4.64m To ...
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| Physics | 3/4/2009 |
Q: 1. (a) A 1.23 kg ball is attached to a ceiling by a 1.92 m long string. The height of the room is ...
A: 1(a) -23.1J (b) 44.4J (c) 0J 2. E = (1/2)kx^2 = 0.032J 3. F = mv/t = 337N 4. mv = Ft = 134kg-m/s ...
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| 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 (a) speed = distance/time = 174/18.8 = 9.26m/s (b) ave. vel. = 58/18.8 = 3.09m/s Q2 v = v0+at so ...
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| Physics | 3/2/2009 |
Q: A model rocket is fired vertically from rest. It has a net acceleration of 15.5 m/s2. After 2.0 s, ...
A: v = at = 15.5(2) = 31m/s S = (1/2)at^2 = (1/2)(15.5)2^2 = 31m so after 2s, the rocket is 31m high ...
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| magnetism and gravity | 3/2/2009 |
Q: i was wondering based on a few small scale experiments of my own if magnetism is actually a stronger ...
A: First of all, you don't get infinite energy as mass increases. It takes energy to get mass to go ...
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| Physics | 2/27/2009 |
Q: How do I differentiate among these terms when answering questions on friction, normal force, F=ma, ...
A: Friction occurs between any two moving bodies. The normal force is the force perpendicular to the ...
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| friction | 2/27/2009 |
Q: Can you explain friction with the real time scenarios and with unfamiliar examples and also suggest ...
A: You can put "friction" into Google or look it up in Wikipedia. There is friction between everything ...
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| friction 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 taught physics several years and I know that the answers in the book are not always correct. In ...
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| Physics (Friction) | 2/25/2009 |
Q: Book: physics Principles and problems 17. A girl exerts a 36 N horizontal force as she pulls a 52 N ...
A: The symbol for coefficient of friction is the Greek letter mu. I'm going to use u. 17. u = 36/52 = ...
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| physics | 2/18/2009 |
Q: a person throws a ball up at 13 m/s. (neglect air friction). what is the acceleration at the highest ...
A: The acceleration is constant throughout the flight, namely, g. The speed at the highest point is ...
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| Height from a shadow | 2/15/2009 |
Q: Presumably at some point the shadow of an object will be the same length as the height of the ...
A: It's not easy to determine the angle of the sun. The easiest way to measure the height of a tree is ...
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| Direction of the acceleration of a charge | 2/12/2009 |
Q: I have a question about the behavior of charges in an electric field. I would like to know how the ...
A: It's really both since the field at a given point is a function of the magnitude of the charge and ...
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| bernoulli | 2/7/2009 |
Q: In the steady flow, what is the factor that decreased the pressure and increased the velocity when ...
A: There's no factor. It's just the fact that, if the fluid is incompressible, like water, then the ...
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| Electric Circuits | 2/4/2009 |
Q: I am somewhat confused by the Formula for Power- P=V*I and Ohm's law which says V=I*R. In the first ...
A: Ordinarily, the voltage is fixed. In the US standard household voltage is 110-115 volts except for ...
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| nuclear fusion | 2/3/2009 |
Q: i want to know what exactly is the hindrance in building a nuclear fusion reactor. I mean , if the ...
A: We get our energy from the sun because of fusion reactions taking place in the interior of the sun. ...
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| Oscillation | 1/28/2009 |
Q: Respected sir I am Mukul chakravarty of class 11 What is the difference between simple harmonic ...
A: no, you could have a square wave that is harmonic and a constant amplitude. It has to be a sine ...
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| Oscillation | 1/26/2009 |
Q: Respected sir I am Mukul chakravarty of class 11 What is the difference between simple harmonic ...
A: Harmonic motion simply means that the motion goes back and forth from some midpoint. Simple ...
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| the speed of electrons | 1/22/2009 |
Q: Do electrons in different atoms orbit the nucleus at different velocities? Do electrons go faster ...
A: Yes,they orbit at different velocities since the velocity is a function of the distance of the ...
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| Waves | 1/20/2009 |
Q: Give an example of transverse wave and longitudinal wave in solids.
A: In a transverse wave the material moves back and forth perpendicular to the direction of wave. That ...
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| magnetic fields and waves | 1/16/2009 |
Q: I'm not exactly sure how to word this. Can a large enough magnetic wave/field more or less ...
A: Magnetic fields don't build up a physical pressure. The strength of electromagetic fields depends ...
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| magnetically generated electricity | 1/9/2009 |
Q: what are the pros and cons of using magnetically generated electricity? ANSWER: It's easy to do. I ...
A: You can generate electricity from falling water, solar, windmills, geothermal, nuclear, and burning ...
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| A lot of petty questions | 12/22/2008 |
Q: I would very much appreciate your help in clearing my doubts.. 1. Energy is defined as the ability ...
A: 1. Energy is only conserved under special conditions. In elastic collisions between two bodies, ...
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| electricity | 12/17/2008 |
Q: 2 bulbs in series of 60w and 100w of 220v .If the voltage in increased to 440v . Which bulb will ...
A: If the bulbs are rated for 220v, then the resistances of the bulbs are 484 ohms and 807 ohms. If ...
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| Coulomb's Law | 12/14/2008 |
Q: I'm having alot of trouble understanding the basics of Coulomb's law. For one thing I can't get my ...
A: Force on +70 = (9x10^9)(70x10^-6)(48x10^-6)/(0.35)^2 -(9x10^9)(70x10^-6)(80x10^-6)/(0.70)^2 (net ...
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| dispersion of light | 12/11/2008 |
Q: . I want to ask you that as we know after rain rainbow is formed when light passes through the ...
A: It takes very special conditions for a rainbow to form. First of all, the weather has to clear ...
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| Conservation of Mechanical Energy | 12/8/2008 |
Q: What exactly is meant by the Conservation of Mechanical Energy and what are a few examples that show ...
A: When you have an interaction between two bodies, Conservation of ME simply means that the ME before ...
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| Why do many physicists insist that gravitation is actually a force? | 12/6/2008 |
Q: What I don't understand is: If gravitation really is an actual force, then why doesn't it work in ...
A: There's no question that Newton's Law of universal gravitation holds, and can be measured. It is ...
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| About Nuclear physics | 12/2/2008 |
Q: The radioisotope U-232 with 92 protons emits alpha particles with an energy of 5.30 MeV and has a ...
A: (a) I get 2.97x10^-10s^-1 (b) I get 3.87x10^14 Bq, 1 Bq is 1 distigration/second (c) I forgot a ...
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| Calculus in physics | 12/2/2008 |
Q: The following is an example problem about using calculus in physics. I have learned calculus, but I ...
A: I sent this problem to a friend and I have not yet heard back from him. My friend, who has a PhD in ...
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| kinetic energy.. | 12/2/2008 |
Q: i an new and i need help with two questions. 1) In billiards(pool), when the cue ball hits another ...
A: 1) That only happens when the cue ball hits the other ball head on. The equation for conservation ...
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| Radioactivity | 12/1/2008 |
Q: A space probe to one of the outer planets is to be powered by a radioactive source containing 2kg of ...
A: You should have recognized that I used 6x10^23 for Avogadro's number instead of 6.022. Using that ...
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| Radioactive activity | 12/1/2008 |
Q: A patient is to be given an injection of iodine-131 in an investigation of her blood volume.2 ...
A: Half-life means that the activity drops by half in that period of time. If the half-life is 8 days, ...
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| Half-life | 11/30/2008 |
Q: What is the formula uses to calculate a) the effective half-life in body of the patient, b) the ...
A: I don't know what you mean by "effective" half-life. The "biological" half-life relates to the time ...
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| velocity | 11/17/2008 |
Q: I've been absent from school for a while cause we moved and when i got to my new school the science ...
A: The standard equation for mechanics is v = at where v is velocity, a is acceleration, and t is time. ...
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| electricity | 11/17/2008 |
Q: I am a bit confused about the relation b/w power, voltage and current as we know ...
A: You can only transmit so much power and P =VI so for the same power if you increase the voltage you ...
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| HELP! | 11/16/2008 |
Q: I'm doing a plan& design lab to investigate how the terminal velocity of a "toy" parachute depends ...
A: Somehow you have to determine the velocity which is the time to fall a certain distance. The only ...
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| HELP! | 11/15/2008 |
Q: I'm doing a plan& design lab to investigate how the terminal velocity of a "toy" parachute depends ...
A: That would not be easy to do with simple equipment. First of all you would have to determine how ...
|
| magnetism | 11/12/2008 |
Q: i have just studied electromagnetism(X standard), but i exactly do not know why certain (or rather ...
A: Magnetism is due to magnetic domains that exist in certain metals and alloys. There are some ...
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| to ask a question | 11/10/2008 |
Q: when we say about electron they are bound to the nucleus but when we discuss about solid metal then ...
A: If you're talking about a single atom, then, yes, the electrons circle the positive nucleus because ...
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| Physics - Energy/Momentum | 11/4/2008 |
Q: A 2kg ball travelling 4 m/s [E] collided with a 4kg ball travelling 5 m/s [W] in an elastic ...
A: Mom. before collision = mom. after collision so (2)(4) +(4)(-5) = 2Va +4Vb Rel. velocity before ...
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| psyics | 10/21/2008 |
Q: What force would you have to exert on a 326-N trunk up a 21.0° inclined plane so that it would slide ...
A: The component of the weight of the trunk down the plane is 326sin(21) = 116.83N The force of ...
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| Electric current on electricity | 10/18/2008 |
Q: Explain why the headlights of a car go dim when the starter motor is used. Bless you ANSWER: A car ...
A: When we buy car batteries, at least in the US, they are rated for so many months, like 60. They ...
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| Electric current on electricity | 10/18/2008 |
Q: Explain why the headlights of a car go dim when the starter motor is used. Bless you ANSWER: A car ...
A: Headlights have a certain resistance, R, and the power dissipated in them is I^2R. When the current ...
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| 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: The only dimension you need is 2.4m tall. The distance from the wall to the base of the pack is ...
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| Parameters of EM waves | 10/6/2008 |
Q: I know that the wave length of EM waves has to do a lot with determining the type or "quality" of ...
A: I told you the speed was the same for all frequencies. The product of the frequency and the ...
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| Parameters of EM waves | 10/5/2008 |
Q: I know that the wave length of EM waves has to do a lot with determining the type or "quality" of ...
A: The EM spectrum consists of gamma rays, x-rays, ultraviolet, visible light, infrared, short radio ...
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| Relative velocity | 10/3/2008 |
Q: A boy standing in a lift that is moving (a) upwards and (b) downwards at a constant speed of 5 m/s ...
A: Sure, initially, the ball was moving up at the rate of 44m/s relative to the boy when the boy was ...
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| Relative velocity | 9/30/2008 |
Q: A boy standing in a lift that is moving (a) upwards and (b) downwards at a constant speed of 5 m/s ...
A: Since the boy is moving down at 5m/s you have -5t=44t-4.9t^2 and t = 10s Why are you giving me a ...
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| "forces & equilibrium" @ mechanics | 9/28/2008 |
Q: Can you please give explaination to the solutions bit by bit in brief ? Because i actually cant work ...
A: If the angle c were 90 degrees or less, the resultant would have a minimum value of 14.14. ...
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| Questions on E&M continued | 9/23/2008 |
Q: 5) (Circuits) How do I determine where the loop crosses a resistor? In the direction of current or ...
A: (5) resistors are circuit elements that can have currents passing through them. The currents can ...
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| Questions on E&M | 9/23/2008 |
Q: please help with a few problems on electric and magnetic field. 1) When 2 objects are in contact, 1 ...
A: (1) I don't know of a method (2) r is the distance between the charge and the point where E is being ...
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| gravitaion | 9/21/2008 |
Q: why is the gravitational potential enrergy of a body on mass m the surface of earth in the ...
A: That's not an equation for PE. The force of attraction between two masses is given by F = GMm/R^2 ...
|
| big bang | 9/17/2008 |
Q: I'm a little confused about big bang theory. How was all the mass of the Universe created at this ...
A: Scientists think that protons and neutrons may be made up of hadrons, quarks, and other strange ...
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| Newton's Laws | 9/17/2008 |
Q: I am in a college algebra-based physics course, and I am having trouble with my homework problems. ...
A: The vertical component of the initial velocity is 4.7sin(40) = 3.20m/s. So the time for it to get ...
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| physics question | 9/16/2008 |
Q: A skier is gliding along at 3.0 m/s on horizontal, frictionless snow. He suddenly starts down a 16° ...
A: the height of the castle wall is (1/2)gt^2 = 19.6m the cannonball has an initial velocity of 20m/s ...
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| making mass from energy | 9/15/2008 |
Q: In nuclear physics we often hear about energy coming from mass e.g.Nuclear bombs and nuclear power. ...
A: Atoms are not made of packets of energy. They're made of protons, neutrons and electrons. Mass and ...
|
| radius of curvature | 9/14/2008 |
Q: sir can you explain me what is meant by radius of curvature of any curved surface? kats
A: If you tied a string to a pencil, held the other end of the string, and rotated the pencil along a ...
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| gravitation | 9/13/2008 |
Q: sir few questions on gravitation 1) the gravitational force is inversly proportional to the ditance ...
A: 1) yes 2) It does move toward the ball but not enough for you to see 3) Because the body is ...
|
| electicity,electrostatics | 9/12/2008 |
Q: 1)electron moves from i) + plate to - plate ii)- plate to + plate. wat happpens to its P.E. 2)what ...
A: 1) an electron is not going to move from + to - by itself. you'd have to add energy to it. going ...
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| physics | 9/10/2008 |
Q: what is the difference between current and voltage? which one has the greatest power?current or ...
A: Voltage is the potential difference between two points in a circuit. I'm sure you're familiar with ...
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| friction | 9/9/2008 |
Q: sir we were doing this practical in physics of finding the coeeficient of static friction using an ...
A: 3) no 2) ideally, your readings should be the same for different weights. However, in this case the ...
|
| circular motion | 8/4/2008 |
Q: sir i want to ask when a stone tied to one end of a string and whirled around in the horizontal ...
A: 1. because gravity acts straight down, perpendicular to the direction of motion. 2. it does come ...
|
| Electrostatics | 7/27/2008 |
Q: I have a question for you. When I study the electrostatics,there is two concepts that I ...
A: First of all, a few electric field lines are just sketched in for convenience. There are an ...
|
| Physical Science | 7/19/2008 |
Q: Most of the radioactivity we personally encounter come from what?
A: We have radioactive C-14 and K-40 in our bodies naturally. There are small amounts of uranium in ...
|
| optics | 6/26/2008 |
Q: my question is that why white light has less energy than voilet light usually given answer is that ...
A: You realize, of course, that white light is not just 7 wavelengths, but an infinite number of ...
|
| Mechanics_force | 6/26/2008 |
Q: Richard, well how force transports? does it seperate when it reaches two parallel ways after it was ...
A: Something has to produce a force. Your body produces a force on the ground which we call "weight". ...
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| energy transports?! | 6/16/2008 |
Q: Richard, well, when we hit a table (example) by our hand, energy created by us is transported from ...
A: That's transfer of momentum. The first ball has momentum of mv. Since each ball has the same mass, ...
|
| 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: The capacitance will be whatever the value of the capacitor is. If you put it in series with a ...
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| magnetic field | 6/10/2008 |
Q: are electrons able to transport between the two poles (north, south)?? thanks for listening ANSWER: ...
A: The result is never neutral. No matter how close the poles are to each other there's still a ...
|
| optics | 6/5/2008 |
Q: sir i wanted to ask two questions related to refraction and apparent depth 1) When light travelling ...
A: 1)Glass is really a supercooled liquid. If the index of refraction is the same then it's as if you ...
|
| in mechanics | 6/4/2008 |
Q: what's the difference between force and energy?? thanks for listening.
A: Force is a vector quantity and when it is applied to a mass it causes an acceleration. F = ma ...
|
| speed of sound lab | 6/3/2008 |
Q: I had some questions about a speed of sound lab. The lab is performed by using a few different ...
A: 1. In the first method you avoid using the distance to the first resonance so it should be more ...
|
| Physics(Electrostatics) | 5/30/2008 |
Q: A charged capacitor has a dielectric slab placed inside the plates. The slab is removed & then ...
A: If C is the capacitance of the capacitor without the dielectric, then the energy stored in the ...
|
| electrostatics | 5/26/2008 |
Q: theThree identically charged particles are placed on the tips of an equalateral triangle. Draw the ...
A: Since the force on each particle will be the same, it's pointless to indicate relative magnitude. ...
|
| 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: If you had ever seen one pick up a car you would know that they are enormous, probably several ...
|
| physics | 5/18/2008 |
Q: what is the relation between, velocity,accelration & displacement a7 what is rms values. i tying to ...
A: velocity is the rate of change of displacement with time. d = vt acceleration is the rate of change ...
|
| Human powered flight | 5/9/2008 |
Q: I saw somewhere, that a human flew a pedal powered helicopter, (it was only about 1 or 2 feet high, ...
A: There's no way a helicopter 1-2 feet high could lift a human. For a fan with a 10 ft. diameter, ...
|
| Polarization | 5/8/2008 |
Q: I would like to know what Polarization is and how it works.
A: light is electromagnetic radiation and vibrates back and forth in all directions perpendicular to ...
|
| Characteristic X-ray spectrum | 5/5/2008 |
Q: Why is the intensity of the characteristic wavelengths of a X-ray emission spectrum much higher than ...
A: An x-ray spectrum has a certain amount of background radiation called Bremsstrahlung. Superimposed ...
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| I think I found the error | 5/5/2008 |
Q: I believe he transposed two numbers while copying the equation for determining the speed: His ...
A: What do you mean "right" answer? Putting in 0.110 means you're assuming the plate was deformed 11cm ...
|
| The metre | 5/3/2008 |
Q: I understand that the metre is defined as the length of the path travelled by light in a vacuum ...
A: The meter was originally defined as the difference between 2 marks on a Pt-Ir bar maintained at the ...
|
| 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) you can find that in a physics text book or the internet 2) nothing will happen 3) different ...
|
| Electricity and Magnetism | 4/23/2008 |
Q: This question has the same information but a different question. A proton having an initial ...
A: The path of the proton is in a plane. Does your expression "ex" mean that the proton is initially ...
|
| Mechanical Advantage of a pulley sestem | 4/21/2008 |
Q: I am a professional Firefighter for the city of Rochester, NY. I have a question involving ...
A: It's a simple pulley system. There are two clues as to why it's 2:1. First of all, the tension in ...
|
| science- physics | 4/21/2008 |
Q: could you please answer these questions beacsue im really stuck in my school work! Should we spend ...
A: Since I have had several skin cancers removed due to long sun exposures when I was young I do not ...
|
| polution | 4/12/2008 |
Q: As recently as 100 years ago a major problem in cities was pollution...IE fecal matter emitted by ...
A: Pure electric cars, using batteries, do not emit any more gases than your electric toaster or razor. ...
|
| Physics | 4/2/2008 |
Q: Q1=Circuit breaker has more advantage than fuse.Explain why? Q2=The filament of electric bulb is ...
A: 1- don't have to pay to replace the fuse 2- it needs to have high resistance 5- resistance increases ...
|
| Forces from motion | 3/25/2008 |
Q: I am not fully understanding motion diagrams. I know that their will always be gravity pulling an ...
A: You will always draw the force of gravity acting straight down. Just draw the various forces, ...
|
| force | 3/25/2008 |
Q: sir thank you first for replying mu previous questions on force sorry for bugging you but since ...
A: 1) an object in water does either float or go to the bottom, nothing in between except for a ...
|
| Nuclear energy | 3/24/2008 |
Q: Regarding the generation of power with the use of uranium: 1. The radioactive waste that is spent ...
A: 1. yes 2. Pu-239 plus a neutron becomes Pu-240 which splits into two pieces like U-236, forming ...
|
| Nuclear energy | 3/24/2008 |
Q: Regarding the generation of power with the use of uranium: 1. The radioactive waste that is spent ...
A: Uranium in nature occurs in two forms, U235 and U238, with less than 1% U-235. They each have ...
|
| nuclear physics | 3/24/2008 |
Q: sir, the argument given for the unstability of radioactive nuclei is that the ratio of number of ...
A: There are nuclear forces holding the nucleus together. If the ratio of neutrons to protons is ...
|
| 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: I have answered over 4000 questions in the past 3-4 years and seldom do I know where they come from. ...
|
| force and gravity | 3/23/2008 |
Q: sir few questions on force and force of gravity 1) Why does inertia of an object depend on mass ...
A: 1) Inertia is resistance to movement so that applies to objects just to get them moving from rest as ...
|
| colors | 3/21/2008 |
Q: 1. What color of visible light has the longest wavelength? The shortest? 2. Why is red paint red? 3. ...
A: 1. red longest, violet shortest 2. because it absorbs the other colors and reflects red 3. sure, ...
|
| Laser Projector | 3/18/2008 |
Q: I was wondering if there is any such thing as a movie type projector that uses laser light, or if ...
A: There are laser light shows but the problem of projecting a movie onto a cloud would be the fact ...
|
| Netwons law | 3/18/2008 |
Q: Imagine a cannon that is free to roll on wheels. According to Newton's third law, the interaction ...
A: It's a question of momentum. Before the cannon is fired, the momemtum of the system is zero. After ...
|
| Properties of Light | 3/15/2008 |
Q: What does a changing magnetic field induce? What does a changing electric field induce? What ...
A: 1. a changing electric current 2. a changing magnetic field 3. since electromagnetic waves range in ...
|
| acceleration | 3/10/2008 |
Q: This seems a simple problem but no one can explain it in a language i understand. If 1 car ...
A: Two standard equations of motion are v=at and v^2 = 2aS where a= acceleration, v=velocity, t=time ...
|
| a Vacuum Chamber Battery concept | 3/8/2008 |
Q: I was thinking lately about vacuum chambers that slowly let compressed air back in through a linear ...
A: Do you expect to get more energy out of the system letting air in that it took to suck the air out ...
|
| energy bonds | 3/6/2008 |
Q: A 120 g block of ice at 0 degrees C is placed in an insulated thermos containing 420g of water at 22 ...
A: If t is the final temperature, then 120(80) +120t = 420(22-t) which leads to a negative t, not ...
|
| transformers | 3/5/2008 |
Q: when a step down transformer is used for stepping down a high voltage of some kilovolts to a few ...
A: Any losses are a function of the way the transformer is made. Obviously, you're running current ...
|
| Projectiles | 3/5/2008 |
Q: IS it possible to calculate the firing angle of a projectile if you are only given the x and y ...
A: For the vertical distance you have y = y0+(vsinA)t -(1/2)gt^2 for the horizontal distance you have x ...
|
| standing wave | 3/3/2008 |
Q: I don't know how to do thisA 40-cm-long tube has a 40-cm-long insert that can be pulled in and out. ...
A: The standing waves occur when the length changes by half a wavelength so the wavelength is 28.4 cm ...
|
| phys | 3/1/2008 |
Q: can you check these answers for me please? thank you VERY much. 1 a. gases are much less dense than ...
A: 1. a, c, and d are correct. b. pressure is inversely proportional to volume (Boyle's Law) 2. 8000Pa ...
|
| Potential energy | 2/28/2008 |
Q: Imagine that you are replacing a tire on your car on a steep hill in San Francisco, and somehow your ...
A: The tire drops a vertical distance of 85sin(14) = 20.8m So mgh = (1/2)mv^2 which gives you 20.2m/s ...
|
| Light - Fading out | 2/25/2008 |
Q: Sir, I am very new to physics, but of late, I have been trying to learn things by reading stuff ...
A: Light is electromagnetic radiation, like x-rays, radio waves, microwaves, etc. Light from our sun ...
|
| Atomic Physics | 2/25/2008 |
Q: Lately I had a question on Atomic physics regarding gamma rays. Beta and alpha rays cannot pass ...
A: a) gamma rays are absorbed by everything, including Al and concrete. However, they are not stopped ...
|
| Downhill physics | 2/22/2008 |
Q: A 70kg snowboarder is cruising straight down a hill at 20 mi/h. The slope of the hill is due south ...
A: Gravity obviously acts straight down. The component of gravity down the 30 degree slope is ...
|
| weight | 2/22/2008 |
Q: sir since i could not get any other experts free to ask this question i am asking this question to ...
A: You could, but you wouldn't get an accurate reading. Spring balances are calibrated with ...
|
| Batteries | 2/19/2008 |
Q: How exactly do batteries work, and could one make an effective battery using hot sauce as a strong ...
A: Your father may be refering to a car battery. They have two electrodes, one is Pb and the other is ...
|
| jumping off a bridge | 2/19/2008 |
Q: Prof. Raridon, Hi. My name is Stella Ramsey. I am in Mr. Swift's 2nd grade class at Lapham ...
A: You must be pretty good swimmers. If you jump off head first you obviously don't want to hit the ...
|
| Batteries | 2/19/2008 |
Q: How exactly do batteries work, and could one make an effective battery using hot sauce as a strong ...
A: Chemical reactions take place inside a battery which convert chemical energy into electrical energy. ...
|
| phyical science | 2/17/2008 |
Q: why does it take longer time for different liquids to evaporate ANSWER: One of the properties of ...
A: No, the boiling point occurs when you heat a liquid up and it evaporates rapidly. For example, the ...
|
| The Conservation of Mechanical Energy | 2/17/2008 |
Q: A 47.0 g golf ball is driven from the tee with an initial speed of 54.0 m/s and rises to a height of ...
A: (a) v^2 = 2gH = 2(9.8)(25.2) so v = 22.2m/s That's the initial vertical velocity which means it ...
|
| physics | 2/11/2008 |
Q: 1) can you give me the nuclear equations for the beta decays of Sr, C, Cs, and Np? 2) Uranium-238 ...
A: 1. Sr-90 -> beta + Y-90, C-14 -> beta +N-14, Cs-137 -> beta +Ba137, Np-239 -> beta + Pu-239 2. ...
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| High Magnetic Fields | 2/8/2008 |
Q: I'm a 3rd year physics student at notts uni, uk. I have a pair presentation on high magnetic fields ...
A: Why do we build bigger and bigger atom smashers? Because you can investigate more things. Same ...
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| collision | 2/8/2008 |
Q: During the filming of a certain movie scene, the director wants a small car (mass 750kg) traveling ...
A: The momentum of the car is 750(35) and the momentum of the truck is 3200v. Afterwards, the momentum ...
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| fission | 2/3/2008 |
Q: sir 1) can you explain why Uranium 235 can not undergo fission with a fast moving neutron or why ...
A: 1) In order for U-235 to undergo fission, it has to capture a neutron and become U-236. The neutron ...
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| Another Physics problems: Pls help | 1/31/2008 |
Q: 1.) A rock is dropped into a 60 meter deep well. Neglecting air resistance how long will it take the ...
A: 1) S = (1/2)gt^2 = 4.9t^2, put in t = 1,2,3 and solve for S 2) v^2 = 2gS = 2(9.8)(2.5), solve for v. ...
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| 8 questions... simple. | 1/31/2008 |
Q: 1. When a solid (1) is heated, it breaks up into a gas and another solid (2). The solids and the gas ...
A: Some of your questions are confusing 1. What do you mean by a "pure substance"? 2. If you start with ...
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| what does watt mean | 1/25/2008 |
Q: I have a space heater that I think is eating up my electricity. I calculated that it pulls 12.5 amps ...
A: watt is a rate, joules/second, so if your heater is on for the whole 24 hours, that's 36 ...
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| static electrcity | 1/16/2008 |
Q: sir i hav few questions on static electricity 1) Why does a chit chat sound is heard when we rub our ...
A: 1) any sound produced is mechanical 2) you don't have to comb your hair in the dark to produce a ...
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| Electrostatics | 1/15/2008 |
Q: A solid metal sphere of radius 5cm and a hollow metal sphere of radius 10cm, each have one coulomb ...
A: For the solid metal sphere E = 9x10^9(1)/0.05^2 = 3.6x10^12 at the surface of the sphere. Just ...
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| 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: I looked at the web site. That's a neat idea but I don't how you're going to be able to do it in a ...
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| physics question | 1/14/2008 |
Q: I recently purchased a motorcycle ramp that has a 500 lb static load limit and I would like to know ...
A: Both a and F are vector quantities and since a is parallel to the ramp F is also. The tires ...
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| water | 1/9/2008 |
Q: If you hold a marble and a brick underwater (e.g., pool), which will hit the bottom faster, or both ...
A: Yes, after dropping a short distance objects reach a terminal velocity which is given by ...
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| electrons and protons | 1/9/2008 |
Q: I was wondering what a negative charge really is. i understand that electrons carry a negative ...
A: Electrons and protons are masses that happen to have opposite charges. That's just the way nature ...
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| electrons and protons | 1/8/2008 |
Q: I was wondering what a negative charge really is. i understand that electrons carry a negative ...
A: Scientists know that atoms are electrically neutral. They know that protons and electrons have an ...
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| electricity | 1/4/2008 |
Q: sir i hav one doubt regarding a numerical in teh following circuit diagram we hav to find teh ...
A: In this case the 20V battery is putting energy into the system and the 8V battery is being charged ...
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| quick question | 1/4/2008 |
Q: I cannot stop thanking you! Your help is so amazing! Just some final questions: You used v=gt ...
A: Well, the time is the same whether you calculate for something dropping or something rising. ...
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| please help! | 1/3/2008 |
Q: I would greatly appreciate any help you may provide to me regarding the following question. I have ...
A: Since the momentum in the x-direction is zero after the collision, 18(25) = 12vcos(60) where v is ...
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| potential difference | 12/23/2007 |
Q: I am learning about electric potential difference, and wonder if my understanding of it is correct. ...
A: In order for 1C of positive charge to move from A to B, B would have to be negative relative to A, ...
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| portable light | 12/20/2007 |
Q: I need assistance with making a portable light for hunting. I have a 12 volt, 3M candlepower ...
A: They don't seem to have a "physics" category or I would sign up for it. Does your light have a ...
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| negative and positive charge | 12/16/2007 |
Q: what exactly is a negative and positive charge. i have always been told negatives and positives like ...
A: Atoms have a nucleus containing protons and neutrons with electrons circling around. Electrons have ...
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| physics | 12/6/2007 |
Q: A sphere of mass 2.8x10^-4 kg is suspended from a cord. A steady horizontal breeze pushes the sphere ...
A: You know F, you know sin(37), you can find T I'm sorry. I assumed you were smart enough to ...
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| physics | 12/1/2007 |
Q: A uniform plank of length 4.1 m and weight 203 N rests horizontally on two supports, with 1.1 m of ...
A: To the left of the right support is 3 m of plank which has a weight of 148.54N. To the right of the ...
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| in need of a trebuchet expert | 11/28/2007 |
Q: I am doing a project on trebuchets, specifically comparing the optimization of medieval trebuchets ...
A: I talked to a friend of mine who knows a lot about trebuchets but doesn't have time to correspond ...
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| physics | 11/25/2007 |
Q: I know you don't answer homework questions but i need someone to tell me how to go about this ...
A: You can write the exponents as 1.5x10^4, 2.3x10^11, etc. From Kepler's Law, T^2/r^3 is a constant ...
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| Atomic physics | 11/6/2007 |
Q: I just had one question. My professor hasn't been explaining this terribly well, and I was hoping ...
A: Air is a mixture of N2 and O2. I presume you know about Avogadro's number, the number of molecules ...
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| Physics | 10/28/2007 |
Q: A battery of e.m.f 15V and internal resistance 2 ohm is connectedto 2 resistors of 4 ohm and ...
A: (a) the current through each resistor is 15/12 = 1.25 amps Watts = I^2R = (1.25^2)(6) = 9.38 J/s = ...
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| E=MC^2 with Hydrogen | 10/23/2007 |
Q: I'm a little confused with E=MC^2 in Hydrogen. If you introduce an electrical field of 13.6 volts ...
A: You can't propel a proton into a helium nucleus. The force of repulsion between positive charges ...
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| flux | 10/12/2007 |
Q: I am working on some practice problems in a book and came across one where i got stuck. Basically, ...
A: Except for the base of the bulb, the light goes out in all directions. It's not enough to just know ...
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| light | 10/11/2007 |
Q: "Clear," light into it's three primary colors (red Yellow blue). My question is this: are the ...
A: In a vacuum, or almost in air, the velocity of every wavelength of electromagnetic radiation, ...
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| light | 10/11/2007 |
Q: "Clear," light into it's three primary colors (red Yellow blue). My question is this: are the ...
A: Visible light consists of electromagnetic energy with wavelengths between 400 and 750 nm. A prism ...
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| question regarding general physics | 10/9/2007 |
Q: (1) Two astronauts are in outer space connected with a rope in a state of complete weightlessness. ...
A: (1) They are not "weightless". Their weight due to the pull of gravity is balanced by the ...
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| Egg Drop project | 10/6/2007 |
Q: what would i have to write in the introduction about a design of the egg drop experiment where the ...
A: You want the socks and the bands to absorb the momentum when the box hits the ground so that the egg ...
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| Physics Help! | 9/15/2007 |
Q: Help would be great!! thank you :) #1 A bicycle travels 3.2 km due east in 0.10 h, then 3.2 km at ...
A: #1 total distance east = 6.4 +3.2sin(15) = 7.23km total distance north = 3.2cos(15) = 3.09km ...
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| physics question | 9/15/2007 |
Q: I need help with this problem, I can't figure it out: A cannonball is catapulted toward a castle. ...
A: The initial vertical velocity is 38sin(45) = 26.87m/s The horizontal velocity (constant throughout) ...
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| Physics question | 9/14/2007 |
Q: I have tried this problem a few times and every time I get the wrong numbers, could you please help ...
A: The initial vertical velocity is 18.7sin(25) = 7.90m/s v^2 = 2gh so 7.9^2 = 2(9.8)h so h = 3.18. ...
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| Question on Gravity | 9/12/2007 |
Q: We often here people talk about "defying" gravitity and "suspending" gravity. Can these words be ...
A: Any object that has mass is attracted to every other object that has mass. We define gravity as the ...
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| Power Savers | 9/12/2007 |
Q: As a student living with 6 others i have been looking at ways to cut down our energy use to save ...
A: It probably just reduces the voltage from 115 to about 100 which means your 100 watt bulb would only ...
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| dimension | 9/7/2007 |
Q: . Is the dimensions are suggested only for length, time and mass? or for all other base quantities ...
A: The basic standards for mass, length and time, generally called the MKS system, since the metric ...
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| Physics | 9/4/2007 |
Q: I am having trouble understanding what to do with the information given in the following equations: ...
A: 1) H = (1/2)gt^2 = 4.9(1.5)^2 = 11.02m v^2 = 2gh = 2(9.8)(11.02) so v = 14.7m/s 2) The package will ...
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| Velocity | 8/28/2007 |
Q: Will different balls have different velocities when they strike the ground?
A: How far are they falling? If it's only a short distance, a few hundred feet, then the answer is ...
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| ballistic pendulum | 8/27/2007 |
Q: Im a in a first year under graduate physics paper, i'm doing a projectile motion experiment with a ...
A: I'm sure you're aware that the pendulum containing the projectile rises above its original position. ...
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| Concrete | 8/26/2007 |
Q: I am trying to determine what is the impact, per square foot, at ground level of a concrete object ...
A: You have an impact area of 0.28 ft^2 so you can calculate the force per unit area. However, you can ...
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| Potential Dividers | 8/26/2007 |
Q: My question relates to the effect of current drawn at a point, say point b, between R1 and R2 in a ...
A: I = 15/(10+x) and 10+x = 10+5R/(R+5) = (15R+50)/(R+5) so I = 15(R+5)/(15R+50) iR = 15-10I = 15 ...
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| Friction force comparison | 8/23/2007 |
Q: I have 2 clothes irons that are weighted the same. One unit slides down an incline at 13 degrees ...
A: the coefficient of friction is the tangent of the angle so in one case that's tan(13) and the other ...
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| electromagnetism | 8/23/2007 |
Q: sir can you explain me why does a current carrying conductor has magnetic field around it. why does ...
A: Do you understand why, if you drop something, it falls to the ground? It's just a property of ...
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| Classical Mechanics | 8/22/2007 |
Q: There are two pulleys with a rope to each one. How come that the tension in the rope and the angular ...
A: As you said, the pulley with just the force is straight forward, with Tr = Ia where a is the angular ...
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| presure | 8/21/2007 |
Q: sir i want to ask few questions on water pressure 1) why does water seeks its own level? 2) In a ...
A: 1) If it didn't it would violate the principle of conservation of energy. 2) The tanks would have to ...
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| Potential Dividers | 8/20/2007 |
Q: My question relates to the effect of current drawn at a point, say point b, between R1 and R2 in a ...
A: Okay. Let R = your unknown resistance that will be parallel with the 5 ohm resistance. Then ...
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| Potential Dividers | 8/17/2007 |
Q: My question relates to the effect of current drawn at a point, say point b, between R1 and R2 in a ...
A: Yes, it always helps to have the whole picture. (d) I = V/R so the only ways you can have ...
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| Potential Dividers | 8/16/2007 |
Q: My question relates to the effect of current drawn at a point, say point b, between R1 and R2 in a ...
A: I gather that Vout is the voltage across R2. Since I = V/R, for zero current, R2 would have to be ...
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| capacitors | 8/14/2007 |
Q: what is edge effect in capactors???
A: The capacitance of a capacitor is proportional to the cross sectional area of the plates and the ...
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| feeling acceleration | 8/2/2007 |
Q: a human can feel acceleration, including rotational acceleration. when on a merry go round which ...
A: 1000 mph is the velocity of an object at the equator as the Earth rotates. The angular acceleration ...
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| electricity | 8/2/2007 |
Q: now there are three wires coming to our home, live , neutral and earth. The live wire in india is at ...
A: The neutral wire is connected to the ground which is defined as zero potential. The electricity is ...
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| physics | 7/26/2007 |
Q: a person standing on a weighing machine sits down with a jerk and the weighing machine shows a ...
A: A weighing machine measures force. Your weight is the force due to gravity pulling your body toward ...
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| water | 7/23/2007 |
Q: Does hot water boil faster that room temp. and/or cold water? Why or why not?
A: Water boils when the vapor pressure of the water equals the air pressure above it. Under standard ...
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| electricity | 7/22/2007 |
Q: why is the terminal voltage(when the current is drawn )of a cell less than the emf (when circuit is ...
A: Simple, if E is the emf and V is the voltage, then V = E -ir, where r is the internal resistance ...
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| potential | 7/18/2007 |
Q: helo sir 1) I was reading the chapter on electric potential. Now the elctric potential in all books ...
A: 1) Why do you think that positive charges can't move? It's true that electrons move through metals ...
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| physics | 7/17/2007 |
Q: when a projectile was fired from a gun, it had initial horizontal and vertical components of ...
A: The horizontal velocity of the gun stays constant throughout its path, disregarding air friction. ...
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| electircity | 7/15/2007 |
Q: I have some questions based on electricity 1) why does a thin wire offer more resistance to current ...
A: 1) It's not the surface area but the cross-sectional area that matters when calculating resistance ...
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| physics-mechanics 2 questions | 7/15/2007 |
Q: random questions out of the text i cannot seem to wrap my mind around. First year University Physics ...
A: 1) let y = height above the window and t = time to drop to the top of the window. therefore, y = ...
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| Atoms | 7/13/2007 |
Q: I was wondering if there is any way to estimate the number of atoms that are in an object, such as ...
A: Sure. the number of atoms in one gram-molecular-weight of a material is 6x10^23. That's 12 grams ...
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| resonance | 7/12/2007 |
Q: sorry sir again i have some doubt in resonance. since you amswered my previous questions very well, ...
A: the frequency does not increase. that's a function of the tuning fork. suppose the wavelength is ...
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| sound | 7/11/2007 |
Q: sir i know that this may not really be related to your field, its related to resonance of sound, but ...
A: 1) Sounds can be broken down into sine waves. If you add together two sine waves with the same ...
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| magnets | 6/30/2007 |
Q: I had a BBQ/picnic at my workplace a few weeks & the game I was in charge of was the duck pond. I ...
A: I assume the magnets on the ducks were little disks. Did you take the other four off and see if ...
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| Electricity | 6/24/2007 |
Q: I would like to know how an electric bulb lights up as soon as the switch is pressed although the ...
A: The same reason you get water out of a faucet as soon as you open it. The pipe is full of water and ...
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| Light | 6/14/2007 |
Q: I hope you are ok. I have always wondered if you have a hollow cube whose internal sides are made ...
A: I'm fine. Right now I'm volunteering at the Science Museum in Oak Ridge, TN. Since there's no such ...
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| Principle of conservation of energy | 6/10/2007 |
Q: a) Explain the relevance of the principle of conservation of energy to: (1)a stone falling from rest ...
A: 1) the stone loses potential energy which goes into kinetic energy. mgh = (1/2)mv^2 2) here, ...
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| Physics-Magnetism | 6/9/2007 |
Q: 1. What happens to the lines of force if unlike poles of two different magnets are placed close ...
A: 1. You have to realize that there are an infinite number of lines of force surrounding any magnet. ...
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| Projectile Motion | 6/8/2007 |
Q: Why do any 2 angles that give the same range in projectile motion add upto 90 degrees? ANSWER: ...
A: If the initial velocity of the projectile is v and the initial angle is A, then the range is given ...
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| magnetic fields | 6/4/2007 |
Q: i have 5 questions that i was wondering if you could possibly help me to answer, they are: 1) ...
A: 1) B and H are related through magnetic permeability B = u0H where u0 is the permeability of free ...
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| Momentum | 5/14/2007 |
Q: A bullet with a mass of 45g is fired into a 8.3 kg block of wood resting on a floor against a ...
A: The energy to compress the spring = (1/2)kx^2 = (1/2)(76)(0.28)^2 = 2.98J which is equal to the ...
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| base and derived uinits | 5/14/2007 |
Q: I think ampere(unit of current) is a derived unit but why it is considered as base unit? please tell ...
A: Here's the definition from a physics book - If two very long parallel wires one meter apart carry ...
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| Time Travel concept | 4/26/2007 |
Q: I am curious about Time Travel. I have read and seen material on the topic. Most tend to sway to the ...
A: Unfortunately, nothing that has mass, including us, can travel with the speed of light. Only very ...
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| Physics Q's | 4/24/2007 |
Q: let me know what you think. 1. hydrogen, with its one electron, can produce a line spectrum with ...
A: 1. The electron can change from one level to another with the visible lines corresponding to an ...
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| metal detectors | 4/22/2007 |
Q: What is the significance of kiloherzs in metal detectors? They range from 10 to 17 Kz., and ...
A: I can't comment on the significance of the frequency. It may have something to do with penetrating ...
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| refraction | 4/22/2007 |
Q: can u explain me why the constituent of white light (the seven colours)though having different ...
A: First of all, there's not just seven colors, but an infinite number going from 400nm to 700nm. ...
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| physics | 4/22/2007 |
Q: what is potential and kinetic energy? Do all amusement park rides have this?
A: Kinetic energy is energy of motion, KE = (1/2)mv^2 Potential energy is energy of position PE = mgh ...
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| Physics | 4/18/2007 |
Q: I was just wondering if you could answer this question for me:"The dam or dike is made thicker ...
A: Just as divers find out, water pressure increases with depth. It should be obvious that water ...
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| electrical conductivity | 4/17/2007 |
Q: A dinner conversation revolved around the question of whether ice or water was a better electrical ...
A: If they're both "pure", they're the same, both poor conductors. Water has be distilled to be free ...
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| Physics | 4/15/2007 |
Q: I once rode on an amusement park ride where riders stand against the inside of a cylinder, once the ...
A: I was on one of those rides with my daughters at Six Flags over Georgia about 30 years ago. It ...
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| Lab Report | 4/14/2007 |
Q: I did on experiment to determine the coefficient of friction of wood on wood. So now I am writing a ...
A: How about a hypothesis that it's going to take some force to pull one piece of wood across another ...
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| Energy due to charge | 4/12/2007 |
Q: Two protons are brought towards each other. will the potential energy of the system increase or ...
A: If two protons are brought towards each other the potential energy increases since it takes work to ...
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| Physics | 4/10/2007 |
Q: A set of parallel plates in a cathode ray tube is 17.8 cm long, and the plates are 3.45 cm apart. ...
A: Yes, you can think of it as firing a gun horizontally and the bullet dropping due to gravity. First ...
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| friction | 4/10/2007 |
Q: frictional force acts to oppose one surface from sliding relative to the other with which it is in ...
A: Friction can be both good and bad. If you're sliding something along a surface you want the ...
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| Incline Plane | 4/10/2007 |
Q: When we learn about Inclined plane, we have two coordintates, mg, mgsin(teta) and mgcos(teta). 1.mg ...
A: mg acts straight down but to calculate the forces acting on a body on an inclined plane, you need to ...
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| Electricity | 4/10/2007 |
Q: I am having difficult with the following problem: Object I has a charge of +3*10^-6 coulomb and a ...
A: The first parts are okay. For the magnitude and direction of the electric field midway, simply ...
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| Mechanics | 4/10/2007 |
Q: I am a little confused with the followingA pendulum consists of a small object of mass m fastened to ...
A: First of all, a pendulum will swing back and forth with a certain period regardless of the angle ...
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| plzzzzzzzz answer me very soon.... | 4/6/2007 |
Q: my questions are Q1. Describe all the forces acting upon a ladder that is leaning against a wall. ...
A: Q1. There is a force that the floor exerts against the ladder and a force that the wall exerts ...
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| Electricity | 4/4/2007 |
Q: I have some follow-up questions from our last exchange: Hi! I have another question from a past AP ...
A: 1) the batteries oppose one another so that's why it's 18. The 2 volt battery is being charged by ...
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| Electricity | 4/4/2007 |
Q: I have another question from a past AP Physics B Exam (I'm preparing for the exam in May!) The ...
A: Yes, the equivalent resistance of the circuit is 4+R so (4+R)(2) = 18 and R = 5 ohms. the ...
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| i want answers very soon. | 3/27/2007 |
Q: Q1. Scientists are told to doubt everything and not believe anything that is not provable. Is this ...
A: Q1. I think it's a strength. Q2. already answered this Q3. Obviously, the angle between the two ...
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| plzzz answer it soon..... | 3/27/2007 |
Q: question is Suppose we measure time by using hour glasses filled with sand. Discuss the various ...
A: Obviously it would depend on how accurately one glass measured an hour. Any error would propagate ...
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| Newton's law of gravitation | 3/15/2007 |
Q: Can you see if my strategy for this problem is a good one or not. First the problem, An object is ...
A: The final velocity is going to be greater than that since g increases as the object approaches the ...
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| mass energy equation | 3/12/2007 |
Q: before u read the questions i apologise for asking so many detailed questions. bUt please do reply. ...
A: 1. I cannot explain E = mc^2 without referring to nuclear reactions since that's the only place ...
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| acceleration due to gravity | 3/12/2007 |
Q: Why is the value of acceleration due to gravity(g) more at the poles than at equators? Why does the ...
A: gravity varies with the distance from the center of the Earth so that's the answer to your first ...
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| physics | 3/5/2007 |
Q: why does an object on mass m gains mass when it travels with the speed of light? I know it is ...
A: It's called relativistic mass since the object doesn't get any bigger in size. Anything with mass ...
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| Velocity of radiation | 3/5/2007 |
Q: What is the velocity radiation in a vacuum? Does the type of radiation effect the velocity? Also, ...
A: Nuclear decay such as nuclear fission, fusion or unstable molecules can produce gamma radiation but ...
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| science project | 2/28/2007 |
Q: My friend and and I are doing a science project and we need to demonstrate momentum. However, we do ...
A: momentum is the product of mass times velocity. M = mv. Some novelty stores sell a momentum ...
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| physics | 2/24/2007 |
Q: Im joyce. am asking for your help.. Sad to say, i can hardly understand Physics sub.. Our topic is ...
A: 1. In physics we prefer to stick to metric units. 1 Hp = 746 watts = 746 joules/s PE = mgh = ...
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| Center of Mass | 2/23/2007 |
Q: I see where the 300=v1+12v2 comes from, but am having trouble seeing how V2-V1=300 was derived.A ...
A: For an elastic collision you have momentum conserved and energy conserved. So you have v1i and v2i ...
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| Elecricity | 2/22/2007 |
Q: When current is flowing in a wire, can we say that wire is charged ?
A: No. When we say something is "charged" we usually mean there's a separation of charge and one part ...
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| physics | 2/18/2007 |
Q: why is a swimmer not hurt, while diving in deep water tank?
A: Why should she be hurt? You're not asking a physics question. I've answered over 2000 questions on ...
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| physics | 2/7/2007 |
Q: why does sound travels slower in denser mediums, for example sound travels faster in wood than steel ...
A: Sound travels as a longitudinal wave in which the molecules bump into each other along the way. So ...
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| physics | 2/7/2007 |
Q: Wha is young's modulus? why are solis considered to have more elasticity than liquids and gases? ...
A: Young's modulus is property of a material, just like density. It's related to stress and strain. ...
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| physics | 2/7/2007 |
Q: The velocity of a wave is given as ?ãE/?ãd where E = elasticity of the medium and d is density of ...
A: Your equation came through garbled. My textbook shows the velocity of sound in a liquid to be ...
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| physics | 2/6/2007 |
Q: what is effective length of a bar magnet? Why is it called so? Why is effective length less than the ...
A: A bar magnet is so called since it's shaped like a bar. It can be any size. It's just the nature ...
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| very simple question | 1/31/2007 |
Q: i have one question, i admit it is simple, but i can take either way on it. does initial velocity of ...
A: No, they are entirely separate. For objects subject to the gravitational pull of the Earth, the ...
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| Physics Kinematics in one dimension | 1/31/2007 |
Q: I am so stumped on this one! Usually, I have a clue about waht equations to start with, but this ...
A: First of all, you need to convert from km/h to m/s. 45km/h = 12.5m/s 65km/h = 18.06m/s A) Even at ...
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| Gauss's Law | 1/30/2007 |
Q: I have a (three-part) question on Gauss’s Law. If you enclose a dipole in a spherical Gaussian ...
A: My book talks about deriving Gauss's Law with a point charge, q, enclosed by a surface S to get the ...
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| Projectiles | 1/24/2007 |
Q: At 1/2 of its maximum height the projectile is 3/4 of its original speed. What is the launch angle. ...
A: If the launch angle is A and the initial velocity is V, then the initial velocity in the x direction ...
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| Physics | 1/22/2007 |
Q: I am sure this is something really easy that I am simply overlooking but here it is: Margaret has ...
A: Let's say the distance upstream or downstream is x. Therefore, the current in the stream is x/8 ...
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| Physics | 1/19/2007 |
Q: A skier is gliding along at 3 m/s on horizontal frictionless snow. He suddenly starts down a 10 ...
A: KE at bottom = KE at top +mgh where h is the height of the incline. Since the mass cancels out you ...
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| please help | 1/7/2007 |
Q: The problem is that there are 2 blocks connected by a string (that has the same mass everywhere in ...
A: First of all, the tension is the same throughout the rope, otherwise it would break. All three ...
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| ball | 12/31/2006 |
Q: how does the height of a ball drop affect the bounce height? what is its independent and dependent ...
A: The bounce height is related to the original height by the coefficient of restitution, e. It's ...
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| Vector & Flux | 12/30/2006 |
Q: The resultant will be vector or scalar? I say the Electric flux is defined as the number of electric ...
A: If you define a certain area, then there's no element in that area that doesn't have electric field ...
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| newton | 12/29/2006 |
Q: Did Newton state his 2nd law of motion as F=Ma OR as F=dP/dt? I know the second is more general ,but ...
A: Newton stated it "The change of motion is proportional to the motive force impressed; and is made in ...
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| Friction | 12/28/2006 |
Q: What is difference between 'sliding' 'rolling' 'slipping' of a body when friction is considered ? ...
A: The forces due to friction vary depending on the motion of the body. Obviously, a rolling ...
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| help plz | 12/21/2006 |
Q: here's thewhy is the water supply tank in a town made at suffiecient ht.?my book says its coz then ...
A: For every 30 feet of height in a water tank the pressure increases by about 15 lb/in^2. Since the ...
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| help plz | 12/21/2006 |
Q: here's theacc to the formula pressure=hdg pressure is independent of the area of the surface on ...
A: the amount of force a block exerts on a surface is a function of the mass of the block, independent ...
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| help plz | 12/17/2006 |
Q: can u plz help me out with this question? when a floating piece of ice melts into water it contracts ...
A: Ice is less dense than water. That's why it floats. Any floating object sinks until it displaces ...
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| physics-simple harmonic motion | 12/15/2006 |
Q: what exactly do u mean by- equation of a simple harmonic motion? what is it's significance?
A: Think of a child swinging back and forth. The projection of the child's path on the ground ...
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| voltage vs current | 12/5/2006 |
Q: i made a lemon battery by connection about 24 lemons in series and get a voltage of about 20 volts. ...
A: It's the chemical reaction inside that produces the energy. Sorry you felt like I didn't give you ...
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| Physics | 12/5/2006 |
Q: 1. Which of the following will result in a chemical change? A. Melting ice to obtain water B. ...
A: I don't know where you're getting your answers but you didn't do a very good job on these. 1. D ...
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| hair dryers | 11/20/2006 |
Q: hey can you please tell me how hair dryers work? and how electricity is invloved in it?
A: Light bulbs get hot in addition to producing light. The elecricity passes through a resistor in the ...
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| Decay Equation for Pendulum | 11/16/2006 |
Q: Richard. That's correct, I'm referring to the decay in height as the pendulum swings. If the ...
A: Sure, e^2 would still be a constant. You must have pretty sharp eyes if you can detect a change in ...
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| Decay Equation for Pendulum | 11/15/2006 |
Q: I'm looking for a basic equation to describe the decay of a swinging pendulum. I remember it ...
A: I assume you're not talking about the period changing as a function of time since that doesn't ...
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| impulse and momentum | 11/13/2006 |
Q: A 1055 kg van, stopped at a traffic light, is hit directly in the rear by a 740 kg car traveling ...
A: let v = velocity of van after collision and c = velocity of the car after collision 740(1.95) = 740c ...
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| inductors | 11/12/2006 |
Q: I understand that an instaneous change in current would imply infinite voltage drop, which doesn't ...
A: Since electricity travels with the speed of light, you can have a near instantaneous change in ...
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| inductors | 11/11/2006 |
Q: I am learning about the properties of inductors. I read that changes in current through an inductor ...
A: It may not make sense to you but that's the way inductors work. The self-inductance in a circuit ...
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| Magnets | 11/10/2006 |
Q: I have been told that a magnetic field is strongest at the poles of a magnet and weakest in the ...
A: Regardless of the size of the magnets the strengths of the two poles are the same. It's simply the ...
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| Fluids & Pressure | 11/7/2006 |
Q: Good evening Mr. Raridon, I'm having some problems with this question, I have (I think) figured out ...
A: Since the density of Hg is 13.6, 1 meter column of water exerts the same pressure on the bottom as ...
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| nuclear power | 11/6/2006 |
Q: i have a few of questions to ask. When exactly will nuclear power run out? how many nuclear power ...
A: Nuclear power will not run out for many, many years, especially if you breeder reactors which create ...
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| work and energy | 11/2/2006 |
Q: Yes I tried it but i am confused the distance from A to B is .500m and the distance from B to c is ...
A: So now you have calculated F(AB), F(BC) and F(AC). mA is being attracted by both mB and mC so the ...
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| Law of Attraction | 11/1/2006 |
Q: Two more quick questions on the subject, since I bought some alloy tuning fork sets and the demo did ...
A: A hollow box helps amplify the sound, especially if you have two boxes and point them toward each ...
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| Law of Attraction | 11/1/2006 |
Q: I'd like to do a simple demonstration of the Law of Attraction (like vibration attracts like ...
A: Yes, another tuning fork at the same frequency will vibrate but they have to be fairly close ...
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| Physics | 11/1/2006 |
Q: A fighter jet is launched from an aircraft carrier with the aid of its own engines and a ...
A: You could write the thrust as 1.90x10^5N and the kinetic energy as 4.10x10^7J The work done by the ...
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| physics help | 10/30/2006 |
Q: The moon has a mass of 7.4x10^22 kg and copletes an orbit of radius 3.8x10^8 m about every 28 days. ...
A: You should be able to answer those. The circumference of the moon's orbit is 2(pi)(3.8x10^8) and ...
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| spin balancing tires | 10/30/2006 |
Q: Just bought a new set of tires and noticed that they caution you never to exceed 35 mph on the ...
A: You might ask your tire dealer. If you are stuck on ice then you're obviously not moving. If your ...
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| Curvature | 10/29/2006 |
Q: A car rounts a banked curve where the radius of the curvagure of the road is R=100m, the banking ...
A: The weight of the car, mg, acts straight down and the centrifugal force acts horizontally. Consider ...
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| Simple Harmonic Motion | 10/29/2006 |
Q: If a particle moves in simple harmonic motion with a frequency of 3.00 Hz and an amplitude of 5.00 ...
A: Total distance = 10 cm let w be the symbol for omega, so that w = 2(pi)f y = Asin(wt) = 5sin[6(pi)t] ...
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| momentum | 10/22/2006 |
Q: Could you explain what momentum is actually? I know it's a mass having a velocity but if someone ...
A: momentum = mv. One measure of momentum is the force required to stop it. mv = Ft which is called ...
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| rotational motion and the law of gravity | 10/19/2006 |
Q: I don't know how to even start the following question. i need few pointers. the question is the ...
A: the acceleration due to gravity will be less at that altitude. 9.8(6370)^2 = a(6570)^2 so a = ...
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| uranium update | 10/18/2006 |
Q: but I'm confused; Not all atoms split? I thought splitting an atom was a natural process and when ...
A: I don't know where you heard that all atoms split, but it's just the opposite. In nature, no atoms ...
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| uranium update | 10/18/2006 |
Q: I asked a question about uranium and what was "enrichment" the other day and would like to ask a ...
A: No, all atoms don't split. In fact, to get energy from a fusion reaction, you have to combine ...
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| conductor | 10/15/2006 |
Q: WHY SHOULD THAT CONDUCTOR/METAL SHOULD OBEY OHM'S LAW?why should any conductor obey ohm's law? ...
A: Ohm's law states that the voltage across a conductor is proportional to the current through it. V = ...
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| physics | 10/15/2006 |
Q: what are the quantum and classical laws that an electron obeys?
A: Each electron in orbit about an atom has four quantum numbers which are determined by the properties ...
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| uranium | 10/15/2006 |
Q: With everything going on in the news I keep coming across the term "enriching uranium" in layman's ...
A: Uranium, as its mined from the ground, consists of two main isotopes, U-235 and U-238. They both ...
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| Atomic Number | 10/15/2006 |
Q: Can you tell me what would happen to the atmoic number and mass number of a nucleus when it emits a ...
A: The mass number of a nucleus doesn't change since positrons and electrons have very little mass. ...
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| physics | 10/12/2006 |
Q: an amuse ment park ride consists of alarge vertical cylinder that spins about its axis fast enough ...
A: I use u for the coefficient of friction since it's really the Greek letter mu. So u times the ...
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| Newton's Law & Rocket Motion | 10/12/2006 |
Q: A rocket is travelling at CONSTANT SPEED. Q1. Is there change in momentum Q2. What is the net force ...
A: If an object is traveling at a constant speed, in a STRAIGHT LINE, then there is no net force acting ...
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| Egg drop | 10/10/2006 |
Q: What basic underlined principals are involved in a typical physics class egg drop?
A: As the egg drops it obeys the laws of falling bodies, v = gt, S = (1/2)gt^2, KE = (1/2)mv^2 and ...
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| physics help | 10/2/2006 |
Q: sorry to bother u again but there is another problem i am unsure of how to solve i have the answers ...
A: You always want to draw a picture of the problem. the ball is in equilibrium which means the sum of ...
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| physics help | 10/1/2006 |
Q: I have a huge exam on Monday and ther are like 3 questions that i can not figure out how to solve. I ...
A: (a) average speed = total distance/total time = (147.2+59.5)/2.1 = 98.4km/h (b) Here you have to use ...
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| Physics | 9/30/2006 |
Q: I am working with some gifted middle schoolers on a Science Olympiad project. In the project ...
A: That's about it. The egg is accelerating due to gravity as it drops. It has to decellerate ...
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