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| Subject | Date Asked |
| Entalphy | 12/8/2011 |
| Q: I am Mr Washington. According to my guidebook, enthalpy is the amount of heat energy in the system. ... A: I'm trying to convince you that you can only measure differences in both enthalpy and potential ... | |
| Entalphy | 12/7/2011 |
| Q: I am Mr Washington. According to my guidebook, enthalpy is the amount of heat energy in the system. ... A: Total enthalpy of a system cannot be measured. Only differences in enthalpy can be measured. ... | |
| Energy | 11/12/2011 |
| Q: Q.1) Define the following 1) Heat Energy 2) Mechanical Energy 3) Light Energy 4) Sound Energy 5) ... A: 1) Everything above absolute zero has heat energy that shows up as the movement of the atoms in the ... | |
| Calorimetry | 10/13/2011 |
| Q: My chemistry teacher insists that calorimeters change temperature at the same rate as the liquid ... A: As you should know, water has the highest specific heat of any material. Since calorimeters are ... | |
| Thermodynamics | 9/22/2011 |
| Q: Sir, How can you best use a spoon to cool a cup of coffee? Stirring-which involves doing ... A: Yes, stirring might add a minute amount of heat but the coffee loses most of its heat through the ... | |
| Heat transfer in metal bowl? | 8/12/2011 |
| Q: Raridon, a friend of mine asked me an interesting question during a dinner prep and I had to admit I ... A: I'm sure it's not true that they didn't heat up at all. Aluminum is a good conductor and also a ... | |
| Chloride concentrations. | 6/22/2011 |
| Q: I am in my last year of High School and for a chemistry project we were titrating samples. My ... A: I don't believe heat would release any chlorine from any of those salts so it's a mystery as to why ... | |
| Gas compression and pressure. | 5/23/2011 |
| Q: My Assumptions: 1. Cooking Gas(LPG), will be in gaseous state at Room temperature and pressure. So, ... A: You may have seen a demonstration using liquid nitrogen. By keeping it in a thermos you can keep it ... | |
| Physics | 3/15/2011 |
| Q: A 20.0 g copper ring has a diameter of 2.54000 cm at its temperature of 0.000 oC. An aluminum sphere ... A: I sent the first copy of this question on to the question pool. It's easy enough to calculate the ... | |
| chemistry | 2/8/2011 |
| Q: what is log?why we take log?what is the significance of log?please give me answer in a clear words ... A: We use logs to simplify some calculations. Logs can be taken for any base, but usually 10. The log ... | |
| Would this be possible with plastic water bottles? | 11/23/2010 |
| Q: I stumbled upon this website and was wondering if it would be possible to create this in my backyard ... A: There's physics behind the idea. If you fill a bottle with water and set it in the sun, the water ... | |
| Absolute Zero - what happens? | 11/16/2010 |
| Q: I have a question related to what happens at absolute zero. My High School science teacher once told ... A: I doubt that your teacher was able to cool something to near absolute zero since this takes very ... | |
| Heat | 7/8/2010 |
| Q: I don't know much about physics or forms of energy, but pretty much all energy ends up being heat ... A: Heat energy is sort of the low end of the scale. Almost all forms of energy, potential, kinetic, ... | |
| Thermodynamics | 5/6/2010 |
| Q: I'm in 7th grade and I go to Middle School. I have been assigned a project that requires me to ... A: I'm retired so I don't do anything regularly on a day-to-day basis. I volunteer here at the science ... | |
| thermodynamics | 5/2/2010 |
| Q: At sea level, what pressure would water need to be kept under in order to raise its temperature to ... A: The reason you can't duplicate my solution is because the vapor pressure of water as a function of ... | |
| freezing vs boiling | 12/11/2009 |
| Q: which would get to room temperature faster 1 ml of boiling water or 1 ml of frozen water? ANSWER: ... A: no, but without that information, you can't answer your question. Obviously, the temperature of the ... | |
| thermodynamic arrow of time | 10/14/2009 |
| Q: As time passes, physicists say the energy in the universe becomes unusable or disorganized. I don't ... A: Entropy is a measure of disorder. Although a few atoms might become more organized, indicating a ... | |
| please help | 9/7/2009 |
| Q: The weight of the block in the drawing is 93.7 N. The coefficient of static friction between the ... A: F = ma = T-0.85mgcos(21) -mgsin(21) T = 271(0.8) +0.85(271)(9.8)cos(21) +271(9.8)sin(21) = 3276N ... | |
| thermodynamics | 9/3/2009 |
| Q: please tell me the difference between heat capacity,specific heat and molar specific heat in a very ... A: Basically, heat capacity and specific heat are the same thing, the amount of heat required to raise ... | |
| Preheating Steel | 8/17/2009 |
| Q: We originally had to preheat 4" thick steel to 225 degrees prior to welding and now we have to ... A: I assume you're talking degrees C. So you're heating from 25C to 350C instead of 25C to 225C. That ... | |
| water temperature | 6/23/2009 |
| Q: i do not know whether i am at right place or not anyhow if io am not right then please guide me. my ... A: Generally, underground temperatures stay about 50F or 10C year around. Obviously, in the summer ... | |
| Thermodynamics | 6/21/2009 |
| Q: can you please help me with one problem that I have in Physics? The problem is: 1 gram of steam at ... A: Let's assume the final temperature is t. So you have 50(3.33x10^2) +50t(4.186) = 1(2.26x10^3) ... | |
| PV | 3/5/2009 |
| Q: Good evening sir, I am venky.my question is that, what is the effect of pressure on a real and on ... A: A gas at STP (standard temperature and pressure) occupies 1 gram molecular volume (22.4 liters) at 1 ... | |
| Energy | 1/26/2009 |
| Q: Using a modern 100ft tall windmill as an example. If 10,000 lbs was tied onto the end of a rope and ... A: Potential energy = mgh where h is the distance the object falls. Since I don't know the energy an ... | |
| terminal velocity | 1/18/2009 |
| Q: I have been reading about the Phalanx gun system which was originally intended to provide a last ... A: Disregarding air friction, the velocity of projectiles coming down is the same as the projectiles ... | |
| 3 Laws of Thermodynamics | 1/13/2009 |
| Q: I apologize in advance for the simpleton question, but I had a high school physics teacher who ... A: The first law is a statement of the conservation of energy - The (heat) energy put into a system ... | |
| Gravity versus Entropy | 1/5/2009 |
| Q: My understanding of thermodynamics is that entropy trumps everything, given enough time. So long as ... A: First of all, mass-energy equivalence only takes place on the atomic level, such as fission in an ... | |
| Temperature and potential always act alike? | 12/18/2008 |
| Q: Raridon, I had always believed that if potential does something in thermodynamics then temperature ... A: I'm not aware of the term "potential" being applied to thermodynamics. There's potential energy ... | |
| Two questions | 12/12/2008 |
| Q: Firstly, is it true that heat is converted to infrared emission for any object with an above-zero ... A: Having taught physics, I'm aware of the right hand rule but not the name Fleming associated with it. ... | |
| thermal volumetric expansion | 12/4/2008 |
| Q: gas expands by 1/273 of its volume for every degree C the temperature rises. To what extent does a ... A: The expansion of liquids vary, depending upon the liquid. There are tables of expansion ... | |
| freezing the earths oceans | 11/11/2008 |
| Q: how cold would the earth have to get for all the earths oceans to freeze instantaneously?is this ... A: Even if the temperature of the Earth were to drop way below 0C instantaneously, the oceans would not ... | |
| Keeping a very small room warm | 10/16/2008 |
| Q: Mr. Raridon, I have a wooden box outdoors. The box is raised a little off the ground, insulated to ... A: Yes, incandenscent bulbs do put out mostly heat and you obviously know not to touch one that's lit. ... | |
| science work | 9/28/2008 |
| Q: .. i need you to help me understand the patterns in group 1-7 in the periodic table..what am i meant ... A: look at the number of electrons in the outer most orbit. For example, elements in group 1 want to ... | |
| thermodynamics and fossil fuels | 7/28/2008 |
| Q: I took physics many years ago, so my notion of 'thermodynamics' may be off, but here goes: can one ... A: If you think of the biosphere as the whole Earth, then changing the chemical energy of the oil and ... | |
| thermodynamics | 7/15/2008 |
| Q: .. 1) In BOYLE's law when graph is plotted between pressure on x-axis and volume on y-axis at ... A: 1) You're plotting PV = RT where R is the gas constant. At constant T, you get a curve of V vs. P. ... | |
| cold bottles | 6/20/2008 |
| Q: I'm currently sat in Iraq and therefore spend a lot of time taking cold bottles of water out of the ... A: If water is very pure (free of minerals) then it can sometimes be cooled below 0C. When it is ... | |
| First law of thermodynamics | 5/19/2008 |
| Q: The first law of thermodynamics states that energy cannot be created or destroyed, it can only ... A: There is no such thing as absolute potential energy. Gravitational PE is energy of position. If ... | |
| 1st law of thermodynamics and perpetual motion. | 3/5/2008 |
| Q: I was just pondering the 1st law of thermodynamics being the reason why perpetual motion is ... A: Just because something is in perpetual motion doesn't mean it's a perpetual motion machine. That ... | |
| Vacuum...energy? | 2/7/2008 |
| Q: One little question here...in old light bulbs...the vacuum sealed ones, how does the light bulb heat ... A: You don't have to be up to 150F to radiate. Everything above absolute zero radiates energy. When ... | |
| Vacuum...energy? | 2/6/2008 |
| Q: One little question here...in old light bulbs...the vacuum sealed ones, how does the light bulb heat ... A: No. The tungsten has a high resistance so it heats up when the current flows through it. The ... | |
| perpetuum mobile | 1/28/2008 |
| Q: I am an Engineering Student at 7th semester, always had good grades at Universiy, also had some ... A: People have worked on perpetual motion machines for several hundred years without success. ... | |
| problem | 12/17/2007 |
| Q: How would i go about conducting procedures, including the materials used to find out what the effect ... A: Adding NaCl to water will lower its freezing temperature. This property is used to freeze ice ... | |
| heat capecity | 12/4/2007 |
| Q: you know that the Specific Heat Capacity of Water (H2O)in 3 phase (ice ,water ,gas) are different . ... A: Yes, it's important, especially in the case of water since it's a very special material. ... | |
| thermodynamics question. | 12/3/2007 |
| Q: OK, my Chemistry teacher always gives us worksheets but never gives us anything to learn how to get ... A: The heat of fusion is simply the heat required to melt something at its normal melting temperature. ... | |
| Fermilab | 10/1/2007 |
| Q: I was checking our Fermilab and I am amazed at the magnitude of this project. Who pays for this and ... A: The government pays for most of this. Physicists can learn a lot about how atoms function by ... | |
| nitrogen fertilizer | 9/12/2007 |
| Q: while reading some of your other answers it dawned on me that if nitrogen is so plentiful, can we ... A: Sure, you can do it, but probably not economically. You would have to liquify the air and then ... | |
| re Q. on energy yeild of a pile of food | 8/28/2007 |
| Q: How do they test a mixed food for the energy count in say calories on food labels. Is there a ... A: One method is to use a bomb calorimeter. You put a sample in a small metal container that is then ... | |
| Size of a Droplet | 7/13/2007 |
| Q: I was wondering on the maximum size a water droplet could reach? I mean if a normal droplet is 1/8th ... A: A physics professor 40 years ago used to do a demonstration using a wash tub with a hole about 18 ... | |
| Light Bulbs Heat | 7/10/2007 |
| Q: With your background, this must be the most stupid question that have ever had. I hope it does not ... A: That is not a stupid question. The amount of electricity used is the same in both cases but a 30 ... | |
| Where does the energy go? | 6/7/2007 |
| Q: I know that energy cannot be created or destroyed, but I really must ask you this question. Suppose ... A: In the period just before WW2, a number of scientists were bombarding uranium with neutrons to try ... | |
| Where does the energy go? | 6/7/2007 |
| Q: I know that energy cannot be created or destroyed, but I really must ask you this question. Suppose ... A: Actually, energy can be created or destroyed. Haven't you heard of Einstein's equation, E = mc^2? ... | |
| plzzz reply me soon..... | 5/22/2007 |
| Q: An Earth satellite so positioned that it appears stationary to an observer on Earth is called a ... A: a) The satellite is about 22,300 miles above the Earth b) You have to evaluate an integral to get ... | |
| boiling water in a closed container | 4/19/2007 |
| Q: there's a video online showing how to boil water in a plastic water bottle (the kind you buy at a ... A: 1. Obviously, you would want to open the cap carefully since there would be a pressure build-up. ... | |
| thermometer vs digital thermometer | 4/12/2007 |
| Q: why is the response time of a digital thermometer(using a thermistor) quicker than that of an ... A: I just answered this for Chris. Are you in the same class? The response of a digital thermometer is ... | |
| Differnece in Nuclear reaction | 3/28/2007 |
| Q: Please tell me the difference between Nuclear Fission Reaction And Fusion Reation. Thanks ANSWER: ... A: That's just the way nature works. When you burn a piece of wood to produce heat that's a chemical ... | |
| Differnece in Nuclear reaction | 3/28/2007 |
| Q: Please tell me the difference between Nuclear Fission Reaction And Fusion Reation. Thanks A: In nuclear fission, an atom such as U-235 or PU-239, when hit by a neutron, splits into pieces. The ... | |
| C of Stainless steel | 3/21/2007 |
| Q: I am a senior high student in Australia. In an inclass practical, we boiled 100 mL H20 and then ... A: The heat lost by the water equals the heat gained by the stainless steel. The heat capacity of ... | |
| Helium filled balloons. | 3/2/2007 |
| Q: When a helium filled balloon is released in the open, how high can it travel assuming no wind or ... A: As a balloon rises, the pressure of the air outside the balloon decreases which makes the balloon ... | |
| ice | 2/26/2007 |
| Q: Recently, on a cold morning, I entered my car and noticed a bottle of water next to the seat. I ... A: It didn't raise the freezing poing. Sometimes, with pure water, like distilled water, it's possible ... | |
| SOAP | 2/22/2007 |
| Q: I've been doing so much research and I cannot seem to find the Chemical Structure of soap? What is ... A: A "soap" is used technically to refer to any salt in which the negative ion contains the carboxylate ... | |
| Thermal Transfer Rate | 1/22/2007 |
| Q: I am hoping that you can help me I am heating a material in an oven at 85 degree Celsius and when I ... A: If you're able to handle it with your bare hands, it must cool off very rapidly since, as you ... | |
| Auto A/C | 1/19/2007 |
| Q: It would be highly appreciated to tell me what exactly –dry bulb temperature -wet bulb temperature ... A: You have two identical thermometers side by side. One of them has a cloth or wick around the ... | |
| Blip in a graph | 1/17/2007 |
| Q: I am Head of Science at a middle school in Somerset and every year when teaching thermal radiation ... A: I presume you are in England? My only thought is that it might be related to the way the probes are ... | |
| Using a microwave | 1/11/2007 |
| Q: ok, so I was messing around and wanted to see what goes on when i stick some metal in the microwave, ... A: the microwave has the same wavelength as the vibrations of the water molecule. putting water or ... | |
| roof | 1/4/2007 |
| Q: why does roofings follow a corrugated design? A: At least where I live not many roofs are corrugated. Certainly not the roofs on houses. My ... | |
| passive heat transfer | 12/17/2006 |
| Q: I am considering using water filled 55 gallon steel drums in my greenhouse for thermal mass. Do you ... A: That's an engineering problem that depends partly on the flow of air around the drum. How are you ... | |
| boiling water in vacuum | 12/14/2006 |
| Q: Could you explain why it is easier to boil liquid water into steam, in a vacuum (at lower ... A: If you dove to the bottom of a swimming pool you would feel the pressure of the water above. We ... | |
| messuring air volume | 12/8/2006 |
| Q: Im interested to know how much air volume is in a car? And what wopuld be the pressure if compressed ... A: it would depend on the size of the car and the can. You could get a tape measure, climb inside a ... | |
| What color candle burns the fastest? | 11/25/2006 |
| Q: My name is Madison Lamm and I am a fourth graded at Wellington Elementary in Wellington, FL. I was ... A: I don't know of any reason why different colored candles should burn differently if they are truly ... | |
| Einstein | 11/22/2006 |
| Q: I am not sure if this is your expertise but I have 3 questions for you. Hopefully you might be able ... A: Einstein made several contributions to physics. He defined special and general relativity, and the ... | |
| wat is the rate of diffusion of noxygen through air ? | 11/6/2006 |
| Q: im just wonderin sir. does carbon dioxide travel fast too.if i decide to close the window and ... A: Carbon dioxide molecules travel slightly slower than oxygen molecules because of the difference in ... | |
| wat is the rate of diffusion of noxygen through air ? | 11/5/2006 |
| Q: iv got a wierd questn. how long oxygen take to move through air at room temp and press. its for a ... A: Oxygen and nitrogen molecules move very rapidly since they are at a temperature of about 300K. Even ... | |
| Increase Salinity in Seawater | 10/30/2006 |
| Q: How can I increase the salinity in seawater having an initial concentration of only 8900ppm? I need ... A: I don't know of any seawater that has a concentration as low as 8900ppm. But let's assume you have ... | |
| Science Fair Project | 10/12/2006 |
| Q: Mr. Raridon, My daughter, Kristen, is doing research for a science fair project on the conductivity ... A: Get a flashlight bulb and rig up a flashlight battery so that two wires can be put into a glass of ... | |
| Water Temperature | 10/4/2006 |
| Q: I'd like to find a scale of water temperatures. For example, what is considered hot water, warm ... A: it's somewhat subjective. Are you assuming what you would respond to? For example, water at 45F ... | |
| melting gold | 10/4/2006 |
| Q: ...i just know logged on to see if i could find what tempature is needed/required to melt gold and i ... A: I would caution you not to try this. Gold melts at 1060C, a very high temperature. You would need ... | |
| Heat | 9/20/2006 |
| Q: will you answer some questions abut the heat of lightbulbs? I am going to do an experiment to see ... A: Some of your questions do not apply but I'll answer as best as I can Name - Richard J. Raridon 1. ... | |
| Liquids clinging | 9/14/2006 |
| Q: When liquids flow down something with an underhanging lip, they "wick" under. Is this surface ... A: I tried to give you an honest answer. You asked a question in the thermodynamic category which did ... | |
| sweat,scald,.. | 8/7/2006 |
| Q: .. sir i was reading some books on thermodynamics... but couldnt find the exact answer for my ... A: 1- When you put a cold object next to a warm object, heat will flow from the warm object to the ... | |
| heat gradients of a system | 8/1/2006 |
| Q: A 100 kg man whose body temperature is 40 celsius stands at some lesser temperature X for some time ... A: Since normal body temperature is 37C, this guy is sick. The number of calories burned is primarily ... | |
| Gravity | 7/29/2006 |
| Q: me again, you answered the last question so well, but this one may be harder. Its been bothering me ... A: the surface of the ocean varies slightly, but not enough to reflect the difference in ocean depths ... | |
| VISABLE LIGHT | 7/21/2006 |
| Q: So from your answer I understand that "light" is a propergated invisable electromagnetic wave ... A: Electromagetic radiation has some particle characteristics as in the photoelectric effect. However, ... | |
| physics | 7/20/2006 |
| Q: no I didn't get any emails. I gave you the wrong email by accident.So I didn't get any answer. ... A: Energy coming from the sun provides 99% of the energy that we use on Earth. A lot of that energy ... | |
| physics | 7/20/2006 |
| Q: how does energy from sunlight provides the energy for lightning in a thunderstorm? A: Energy from sunlight provides 99% of the energy used on Earth, for all purposes. Lightning results ... | |
| physics | 7/18/2006 |
| Q: I was hoping you can help me with these two questions I'm having hard time trying to answer. THanks ... A: The Kelvin-Planck statement of the second law states: It is impossible for an engine working in a ... | |
| Thermal infrared imageries | 7/13/2006 |
| Q: What is meant by the term thermal infrared imageries? A: Infrared radiation is outside the visible region so we can't see it. Usually it's referred to as ... | |
| re: the atmosphere | 7/13/2006 |
| Q: Can you tell me the difference in the next 2 scenerios regarding the speed at which earth's ... A: For one thing, the oxygen content is not going to change appreciably from the 21% we have now. The ... | |
| presuure and temprature | 7/5/2006 |
| Q: can steam be heated to a temprature more than 100 degress say to 110-130 degrees at atmospheric ... A: Water has a certain vapor pressure which increases as the temperature increases. Under a pressure ... | |
| plasma | 6/24/2006 |
| Q: I ran across a sight the other day about plasma technologies, and it seemed very interesting to me. ... A: Well, you know about solids, liquids, and gases. The main difference is temperature. For example, ... | |
| Resistivity | 5/21/2006 |
| Q: What is resistivity A: Resistivity is a measure of the amount of effort it takes to move electrons through a material and ... | |
| Resistance in a wire | 5/21/2006 |
| Q: I am writing a piece of work about resistance in a wire and I have a few questions. Firstly, with ... A: Each atom has protons in a nucleus and electrons that travel in orbits around the nucleus. Atoms ... | |
| Thermodynamic problems and concepts | 5/2/2006 |
| Q: My name is Georgia Gatner, and I am currently taking high school physics through a distance leraning ... A: 1) You have to do it in three steps. First, you have to warm the ice up to 0C, then melt it, and ... | |
| pressure measurments | 4/22/2006 |
| Q: 1. What is the meaning of "inches of water", and what is its eqiuvalent in psi or in any pressure ... A: Atmospheric pressure = 14.7 lb/in^2 which means the air in a column with an area of 1 square inch ... | |
| difference between temperature and pressure | 3/20/2006 |
| Q: Ok. So what is internal energy. Is it the energy inside the atoms ie energy of electrons . And is ... A: Electrons do orbit about the nucleus of an atom but very little kinetic energy is associated with ... | |
| difference between temperature and pressure | 3/20/2006 |
| Q: Exactly. Heat is transferred by conduction which is actually molicules hitting your hand which ... A: Temperature is a measure of the internal energy of the atoms or molecules in a substance. In a gas ... | |
| difference between temperature and pressure | 3/18/2006 |
| Q: In text books it's written that pressure is actually the total kinetic energy of molicules. In a ... A: Pressure in a gas is the net effect of the molecules hitting the surface of the container. Pressure ... | |
| Freezing point of coca cola | 3/15/2006 |
| Q: This morning my two year old daughter turned up the temperature in our fridge to the maximum ... A: Some things which are mostly water freeze at slightly different temperatures because of sugar or ... | |
| Hello | 3/5/2006 |
| Q: I have a question about light. What is light exactly? lol. I know that sometimes when something is ... A: "light" does not have mass. It has energy and momemtum. Some light comes from electrons moving ... | |
| Hello | 3/5/2006 |
| Q: I have a question about light. What is light exactly? lol. I know that sometimes when something is ... A: When most people say "light" they mean light that they can see. Visible light is only one very ... | |
| hello | 3/4/2006 |
| Q: ok so i have this project about the boiling point of water but i dont need some help on it. I need ... A: Since I was out of town and didn't read my e-mail until 10PM EST, you may not get this in time. I ... | |
| "atomic fire" and sources of thermal energy | 3/3/2006 |
| Q: What is meant by the term "atomic fire"? Besides fire, lava, and magma, solar (also called ... A: "atomic fire" usually refers to a nuclear reactor where the energy comes from splitting atoms. ... | |
| Electrolysis of H2O | 3/3/2006 |
| Q: Raridon, I'm trying to replicate the electrolysis of water to extract the oxygen (I.e. the salt ... A: 1- you don't have to use precious metals, copper wire will work. 2- trial and error 3- may take ... | |
| Electrolysis of H2O | 2/8/2006 |
| Q: When performing electrolysis of water, what affects the output of Hydrogen and Oxygen the most? Is ... A: It's been a long time since I've done this experiment. First of all, table salt would be better ... | |
| Specific heat | 1/30/2006 |
| Q: I am trying to help my 8th-grader with his science fair project. I suggested the topic of ... A: By an EM component, do you mean electromagnetic? Both heat (infrared) and visible light are ... | |
| Science Fair Project | 1/28/2006 |
| Q: I'm in the 7th grade and I'm doing a science fair project. My topic is "How does cell phone ... A: You can't do an experiment on this for a science fair project. It's far too complicated and ... | |
| Fire | 1/28/2006 |
| Q: My understand ing was that Yes where there was smoke certainly yes there was fire but don't you need ... A: If something burns completely to produce carbon dioxide and water vapor then you don't see smoke, ... | |
| za | 1/13/2006 |
| Q: I am doing an essay on organic compunds. The question was "Describe the Variety and importance of ... A: There are many, many varieties of plastics, polyethylene, polypropylene, styrofoam, styrene. Other ... | |
| Dehumidification function - 84 pints per day dehumidification | 1/7/2006 |
| Q: Another aspect of my case that I ignored was the dehumidifaction function of my Air Conditiner. ... A: You can't compare % humidity to pints/day. Relative humidity simply shows how much moisture is in ... | |
| Heating water | 1/4/2006 |
| Q: I am building a trough to heat water which in turn will be heating a composite decking material. The ... A: You will be heating 10.5 ft^3 of water with a mass of about 64 lb/ft^3. 1 Btu will raise the ... | |
| heated air. ( hot air!!!!! ) | 12/18/2005 |
| Q: Can you answer 2 related questions? No1.. It's been 3 degrees frost over night and as the sun rises ... A: You're just seeing water vapor coming off your walls, just like you can see a cloud in the sky. ... | |
| projectiles thrown horizontally | 12/17/2005 |
| Q: I hope I'm finding you in the best of health. By projectiles, when throwing something ... A: If the initial x-component of the velocity is zero, it wouldn't go anywhere. If you fire a rifle ... | |
| coefficient of friction formulas | 11/26/2005 |
| Q: I hope I'm finding you in the best of health. A 60kg boy is on a 15kg sled. He is pushed along a ... A: Yes, Fapplied = 134N Basically, you have to overcome the force of friction which always acts ... | |
| physics | 11/11/2005 |
| Q: Our sun rotates in a circular orbit about the center of the Milky Way galaxy. The radius of the ... A: (a) v = (2.2x10^20)(1.2x10^-15) = 2.64x10^5 m/s (b) time = circumference/velocity t = ... | |
| pressure and energy | 11/3/2005 |
| Q: The case of external pressure compressing a gas appears to be different then. It seems the majority ... A: An increase of kinetic energy in gas molecules is indicated by an increase in temperature of a gas. ... | |
| Infrared and thermal imagery | 11/3/2005 |
| Q: I have some questions on Infrared and thermal imagery. I just want to check does IR detector and ... A: Every object that has a temperature above absolute zero emits energy in the infrared range. A ... | |
| pressure and energy | 11/3/2005 |
| Q: My question relates to the work done by pressure on a condensed system (solid or liquid). Say you ... A: It takes a huge amount of pressure to reduce the volume of water, or any other liquid. That's ... | |
| what does negative work mean? | 10/30/2005 |
| Q: I am trying to get a grasp on the concept of negative work. Say I pick up an object (mass = m) and ... A: You did work W=mgh against the Earth's gravitational field and you increased the potential energy of ... | |
| Thermodynamics | 10/30/2005 |
| Q: 1-A steel sphere with a mass of 161.74 g is placed in an atmosphere of steam at 100degree celcius ... A: 1- heat gained = 161.74(.46)DT where DT = temperature change heat lost = 1.24(2257) heat gained = ... | |
| dry ice on a keg | 10/28/2005 |
| Q: So i was thinking of using dry ice to help to keep a keg of beer cold with some regular ice. I know ... A: If the keg were completely full you might freeze it cold enough to cause the keg to crack but it's ... | |
| physics | 10/24/2005 |
| Q: The weight of the block in the drawing is 65.8 N. The coefficient of static friction between the ... A: The force applied by the hand has two components, one perpendicular to the wall (the normal force) ... | |
| physics | 10/18/2005 |
| Q: WHERE DID YOU GET THIS FORMULA FROM? OR HOW DID YOU KNOW TO DO THAT? A student presses a book ... A: If the book doesn't fall, then the sum of the forces acting upon it add up to zero. The weight of ... | |
| free fall | 9/23/2005 |
| Q: A tennis ball is thrown straight up with an initial velocity of +22.5 m/s. It is caught at the same ... A: g is the acceleration due to gravity which acts on the ball both going up and coming down. It slows ... | |
| velocity vs. acceleration | 9/22/2005 |
| Q: I hope I'm finding you in the best of health. I have great difficulty answering velocity and ... A: velocity and acceleration are both vectors and both can have positive and negative values. ... | |
| I want to rig up a simple... | 9/14/2005 |
| Q: I want to rig up a simple device that will measure temperature 1 foot under soil. The temperature ... A: The accepted terminology now is Celcius, not centigrade. The thermometers that you would stick into ... | |
| Thermodynamics | 9/7/2005 |
| Q: Given a large amount of ice at 25F/-4C, basic salt, and a container of homemade ice cream mixture at ... A: The lowering of the freezing point for a salt-water mixture depends upon the concentration of salt. ... | |
| Adiabatic process | 8/29/2005 |
| Q: according to adiabatic process, the adiabatic compression on a system causes the temperature to rise ... A: 1. Work done on a gas increases the energy of the molecules of the gas and they move faster. ... | |
| Expansion/Compression of Liquids | 8/24/2005 |
| Q: I'm doing some work on a motorcycle brake system and was wondering why fluids are incompressable but ... A: Gases are easily compressable since there's a lot of room between molecules. For example, a volume ... | |
| Creationism | 8/13/2005 |
| Q: Raridon, I believe that I read somewhere that there is a law of Thermodynamics which states that, ... A: Sure, it's impossible for matter to be produced from nothing. However, most scientists believe that ... | |
| Heating a room | 7/15/2005 |
| Q: I have a problem I've been trying to solve for many months, but as it's been over thirty years since ... A: This is a fairly complicated engineering problem that I can't tackle. 2400 watts is a pretty hefty ... | |
| Oxy-acetylene expansion rate? | 7/7/2005 |
| Q: Well see I have all the data. I was just wondering what is the expansion rate of the gas. It is ... A: Oxy-acetylene is actually a mixture of oxygen, O2, and acetylene, C2H2. The combustion reaction is ... | |
| Specific Heat | 5/4/2005 |
| Q: 1- How would the measured value of the specific heat be affected if some boilling water were carried ... A: 1- might change the weight of your sample 2- again, it might change the weight 3- if the temperature ... | |
| Why do bubbles pop | 4/26/2005 |
| Q: I am trying to help my 11 year old daugher with her science fair project. We have been researching ... A: I don't believe surface tension is making the bubbles pop. It's the reason the bubble is round and ... | |
| Temperature | 3/27/2005 |
| Q: How do people get things down to extremely low temperatures such as those required for ... A: That's the science of cyrogenics which you can read about. The reason we can't get to absolute zero ... | |
| matter | 3/25/2005 |
| Q: How many more kinds of matter instead of solid, gas,liqued. please tell me with examples. Q.2. ... A: There are two more kinds of matter, plasma, which exists at very high temperatures, and ... | |
| Liquid Nitrogen | 3/21/2005 |
| Q: How do you create liquid nitrogen and how do you keep it so cold? A: If you're going to lower the temperature of anything you have to remove heat. You put water in the ... | |
| electric felds | 3/15/2005 |
| Q: an electron with an initial speed 5.00 * 10exp6 is projected into a uniform electric feild the ... A: I presume you mean 5x10^6 m/s so it will take 4x10^-9 s for the electron to go 2cm. During that ... | |
| Physics | 3/6/2005 |
| Q: (a)Calculate the force required to accelerate a fire engine from 10km/h to 50 km/h over a distance ... A: Rounding off, you should get 2.78m/s and 13.89m/s but that's a minor matter. Everything needs to be ... | |
| Mechanics | 3/3/2005 |
| Q: If a helicopter were to hover in the air long enough, is it possible that the earth's rotation would ... A: The helicopter has the same angular velocity as the ground beneath it as it takes off and will keep ... | |
| Kinetic energy | 2/28/2005 |
| Q: Th higher the temperature the higher the kinetic energy right? Well if so , then evaporation would ... A: Chemical bonds don't break when a liquid becomes a gas. There are H20 molecules in liquid water and ... | |
| Freezing Water | 2/5/2005 |
| Q: We are supposed to predict what will happen when boiling water is thrust from a pot into the air at ... A: Nothing is going to happen instantaneously. Water will not freeze until the temperature of the ... | |
| Could you pls take a look at this question? | 1/25/2005 |
| Q: This is something related to thermodynamics. I cannot figure this one out. The question is Two ... A: Since you don't know anything about the tank you have to assume that its volume is not going to ... | |
| Freezing Water | 1/22/2005 |
| Q: Is it true that you can make ice cubes faster if you stat with hot water? A: No. The rate at which the temperature changes is related to the difference in temperature. ... | |
| Freezing water | 11/28/2004 |
| Q: My friend recently told me that boiling water will freeze faster than normal temperature water.Is ... A: Suppose you set a dish of water in your freezer with a thermometer in it and measure the temperature ... | |
| uranium | 11/18/2004 |
| Q: If the world is millons of years old , why then is there any radio active matterial left when it ... A: The Earth is estimated to be about 4.5 billion years old. That's also the approximate half-life of ... | |
| Steam and Kinetic energy | 11/16/2004 |
| Q: How do I find the kinetic energy of steam? I am trying to design a steam engine boiler and cannot ... A: Kinetic energy is the energy of motion. Steam molecules have kinetic energy but you can't just add ... | |
| Physics Problem... | 10/31/2004 |
| Q: How do I show the following statement is true. If possible, I need to kno as soon as possible. ... A: I proved this when I was teaching a physics class a few years ago but I've forgotten the details. ... | |
| why does water evaporate on the surface | 10/27/2004 |
| Q: Follow up question to your answer below: why does a liquid water molecule then stay on the ground, ... A: There is no difference between a liquid water molecule and a gaseous water molecule. They are both ... | |
| boiling water | 10/25/2004 |
| Q: How to calculate energy required to keep water boiling for a period of time. Hurricane loss of power ... A: You don't calculate the power required to raise water from one temperature to another, you calculate ... | |
| Determining energy produced from boiling a solution | 10/21/2004 |
| Q: How can I determine the energy produced by boiling a solution based on its boiling point, volume and ... A: Boiling a solution doesn't produce energy. It takes energy to cause a solution to boil, called the ... | |
| Distilled Water | 10/20/2004 |
| Q: My name is Michael and I am an 8th grade student. I am doing a project on superheating. Does ... A: If water can be heated to a temperature greater than 100C under normal atmospheric pressure, then it ... | |
| why does water evaporate on the surface | 10/16/2004 |
| Q: Raridon, Thank you very much for your answer! What would interest me more thoroughly is what occurs ... A: The average energy of molecules is simply a function of the average temperature of the material. ... | |
| why does water evaporate on the surface | 10/12/2004 |
| Q: is it known what occurs with water on the surface of a pond when it evaporates? does it locally heat ... A: In this case we're talking molecules, not atoms. Although the average energy of any water molecule ... | |
| Uniform Circular Motion | 9/20/2004 |
| Q: I thank for your help on the last question, but it turns out I ended up solving it on my own. I sat ... A: the particle makes one revolution in 20 seconds. the circumference = 2(pi)(3) so the speed of the ... | |
| Frame of reference and unit vector | 9/17/2004 |
| Q: I'm sorry about that. Ship A is heading south.Hi again, First of all I would like to thank you for ... A: The position of A as a function of time = 2.5i+4.0j-22jt The position of B as a function of time = ... | |
| Kinematics Review for 1A Engineering | 9/14/2004 |
| Q: ------------------------- Followup Question - Thank you for helping me solve my first problem. I ... A: The initial velocity is not 8m/s, that's the average velocity (total distance/total time). Let h = ... | |
| Kinematics Review for 1A Engineering | 9/14/2004 |
| Q: I'm a first-year engineering student having trouble with the physics review given to me. Here's the ... A: 161km/h = 44.72m/s 29km/h = 8.056m/s You didn't specify ... | |
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