It's the physical property that indicates the degree/intensity of heat present in a substance or an object. It can be expressed and measured according to various scales.

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Why do rotating devices make air colder? [duplicate]

I end up thinking this question frequently recent days. It seems an easy question but i cannot find the answer. You could say "faster the air, cooler it becomes" in that case i am expecting an ...
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Prove that negative absolute temperatures are actually hotter than positive absolute temperatures

Could someone provide me with a mathematical proof of why, a system with an absolute negative Kelvin temperature (such that of a spin system) is hotter than any system with a positive temperature (in ...
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69 views

Is temperature the speed of electrons?

Back in the middle school (which I guess was about 10 years ago) I remember being taught that the temperature of an atom is basically the speed of electrons circling the nucleus which kinda made sense ...
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Ice bath is always 3C, why?

I've always learned that a mixture of ice and water should reach equilibrium at approximately 0C. I've actually tried to create that a number of times in different contexts and always fail. First, ...
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A draft makes people feel cold. How can that be measured?

On some days our office feels very cold to the point at which we find it difficult to type because our hands have gone numb. But our facilities manager insists it is the same temperature as always. ...
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What is the effect of an increase in pressure on latent heat of vaporization?

What is latent heat of vaporization ($L_v$) in the first place? Wikipedia seems to indicate that it is the energy used in overcoming intermolecular interactions, without taking into account at all any ...
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How does liquid convert to gas on getting thermal heat energy?

Say for example, when we heat, water converts to steam gas. How does it happen? What happens underneath giving rise to breaking of bond between molecules in liquid state and spreading them in gas ...
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2answers
174 views

How does temperature relate to the kinetic energy of molecules?

In ideal gas model, temperature is the measure of average kinetic energy of the gas molecules. If by some means the gas particles are accelerated to a very high speed in one direction, KE certainly ...
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1answer
83 views

What is the overall rate of heat conduction through two pipes of different dimensions if the thermal conductivity is not constant?

I am trying to work out how I would find the rate of heat transfer through two pipes made of the same material that are joined at their ends but which have different cross-sectional areas and lengths. ...
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139 views

What causes a heat generating source to stabilize at a certain temperature? (Answered by myself, I think)

For example, we out a heat sink on a microprocessor to keep it cooler. I understand that if we run 100 watts of electricity through the microprocessor, it will generate 100 watts of heat, or 100 ...
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1answer
24 views

When to use Kelvin over Rankine and vice versa

Kelvin and Rankine are both used by scientists over Celsius and Fahrenheit to record heat, but are they both used interchangeably, dependant on the country or preference of an individual, or are there ...
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Why does hot water clean better than cold water?

I had a left over coffee cup this morning, and I tried to wash it out. I realized I always instinctively use hot water to clean things, as it seems to work better. A Google search showed that other ...
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unchanged temperature of balloon inside freezer

I'd tried to put a balloon in the freezer and after enough time (several hours), I took it out and noticed that as I touch it that it's temperature did not drop down . I took an empty balloon ( not ...
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62 views

Calculating the Surface Temperature of the Sun with a Metallic Strip from the Surface of Earth

I am trying to calculate the surface temperature of the sun with a copper strip. I have a temperature sensor to calculate the temperature of the strip and that's it. Assuming the rate at which energy ...
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3answers
150 views

How is heat transferred to a thermometer?

Quick question. I can't seem to find a satisfactory answer online. How does a thermometer measure the average kinetic energy of atmospheric air? I assume that the energy is transferred by molecular ...
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1answer
66 views

Can electrons reflect light?

Lately, I have been watching sparks while connecting my electronic devices and I can notice that electricity is kind of blue, and theoretically it's blue because it reflects blue wavelengths?? And ...
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5answers
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Why less temperature at high altitude

Why there is always cold at high altitudes. e.g. at peak of mountains. Also as we go high from sea level, temperature starts decreasing. Why is it?
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5answers
22k views

Does wrapping a wet paper towel around a glass bottle really speed up the cooling process?

There are claims like this one that you can improve the cooling speed of beverages when you put them wrapped in a wet paper towel inside the refrigerator/freezer. I've just tried it by myself and ...
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6answers
4k views

Can UV light make us invisible?

For an object to create different EM waves, it needs to increase the temperature, so what if we or some material could be so hot, that it would emit ultraviolet light, and thanks to that be invisible ...
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27 views

What does temperature coefficient of resistance depend on?

I tried looking up on Google if there was an expression for the temperature coefficient of resistance(TCR) of a material in terms of other fundamental factors, but couldn't find any. Specifically I am ...
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2answers
196 views

Can temperature be a complex number?

Is it possible for a temperature to be a complex number? I want to say "no" but I can't be so sure. If it is possible I would like to know of an example. I found an interesting article which treats ...
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1answer
89 views

Will my coffee end up colder if I wait to put in the milk? [duplicate]

When I receive a cup of coffee, and I'm not yet ready to drink it, will it lose less heat if I immediately add the milk, rather than wait to add the milk just before I drink it? (Bonus points for ...
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4answers
803 views

What's the basic difference between heat and temperature?

Temperature is usually seen as a calibrated representation of heat but what about latent heat? Eg. Ice and water have different amounts of heat at 0 degree c.
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What type of relationship should the speed of sound vs. air temperature graph have? Linear? Quadratic? Exponential? [duplicate]

I did a lab in class and the data I got might be a bit skewed (this is homework). When I graphed the speed of sound (m/s; y-axis) vs. air temp (degrees Celsius; x-axis), my graph resembled that of the ...
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How can I estimate the cooking time of a roast?

I never remember what worked before, or to write it down someplace. In any case the size and starting temperature will vary. The instructions I learned from refuse to give a time at all, and the ...
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2answers
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Is there any relation between temperature dependence of resistance and fermi energy in metals?

Given that the resistance varies linearly with temperature in metals, is there any way we can calculate the Fermi energy from this information?
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Gay-Lussac's Law & the Patriots

This may be a question better suited for xkcd what if? section...but here goes: with all the hoopla around the patriots / colts game and allegations of cheating by deflating footballs, I've read/heard ...
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1answer
38 views

Will an object with a higher temperature lose its heat faster than a cooler, yet warm object

I'm after the math, which I don't understand yet and can't find elsewhere. The variables are: Two identical cups, A and B The same volume of fluid is contained in each cup, test fluid is water. ...
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1answer
21 views

Convert Temperature into Speed/Kinetic Energy

If the temperature of an object is simply a measurement of the average kinetic energy of the molecules within it; is it possible to convert the temperature of an object, given it's volume, into either ...
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2answers
412 views

Is there a highest temperature? [duplicate]

Im new to physics and do not yet know of all of the terms and math. I was wondering about temperature. I read that there is the lowest temperature which is absolute zero where nothing happens, i.e. ...
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The difference between heat and temperature

So as I understand it, heat energy of an object is the SUM of all the kinetic energies of the molecules of the object (upto constant factor). The temperature on the other hand is the AVERAGE of the ...
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1answer
73 views

What happens as you approach/cross the Planck temperature?

According to IFLScience, above the Planck Temperature (absolute hot) conventional physics break down. My question is what happens as you approach this temperature, and, if it is possible, what ...
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2answers
37 views

Heating suprecritical water in a closed water tank

How does the pressure of water in a closed tank evolve in the following setting: - closed tank of 2 liters (filled up with water) - water initially at 25°C and pressurized to 3 bars The water is now ...
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1answer
167 views

Newton's law of cooling for the heat equation boundary condition

Newton's law of cooling says the temperature of an object satisfies $$ \frac{dT}{dt} = -k(T(t) - T_0),\tag{1} $$ where $T_0$ is the surrounding temperature. See these HTML notes for example. Now if ...
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1answer
144 views

How hot is Plutonium-238 in Radioisotope Thermoelectric Generators (RTGs)?

As I understand it, Plutonium-238 is used to provide power through heat generation in radioisotope thermoelectric generators. My question is... how hot is a pellet of Plutonium-238? Does the heat ...
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9 views

Permeability drop

I'm doing some experiments with Transponder coils with unknown ferrite core. Is there any place I could find Permeability-temperature graphs for all ferrites? Thanks
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6answers
868 views

Why does the bathroom become hot after a bath?

I have noticed many times that whenever I enter into the bathroom just after someone else bathed the temperature inside it would be high. Is it that the body heat comes out when we pour a lot of ...
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6 views

Velocity Selective Coherent Population Trapping and recoil limit on temperature

I have read that it is possible to go under recoil temperature limit using VSCPT (Velocity Selective Coherent Population Trapping) and that this method is based on atoms trapping in quantum state in ...
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4answers
80 views

What is the lowest level things have temperatures?

Something can be cold. If you split it in half, it will still be cold, keep doing that and it will still be cold. My question is, what is the lowest level things can have temperature? Do atoms have ...
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3answers
526 views

What is the logic behind the Fahrenheit scale?

The Fahrenheit scale is defined by fixed points on the scale. What interests me is the apparent arbitrary chosen numbers in these fix-points. First wikipedia wites from 32 to 212. -and later in the ...
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3answers
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Does Time change over temperature? [duplicate]

I am not a physicist, I am just an engineer. But I dared to ask whether the temperature changes the perception of time. Let's consider a particle that "stops" at absolute zero. I was thinking as a ...
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33 views

Am I very wrong with my grey body calculations?

I'm trying to calculate the maximum heat that an object on the moon can reach with the energy provided from Sunlight. I've got a total power output of the sun per square meter at the distance of the ...
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1answer
36 views

Inconsistencies between reported temperatures for objects on the surface of the moon

I'm involved in a bit of a debate over the temperatures of different objects on the surface of the moon during the moon landings. I've seen it said that the cameras only had to survive around between ...
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2answers
64 views

How fast will 1 Liter of 65°C water get back to 20°C?

I want to make a very simple example for a PID controller (to learn and understand it). I thought of a controller for a water boiler. 1 liter of water in the boiler is in a 20°C room (fixed ...
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1answer
93 views

Does time freeze at Absolute Zero? [closed]

Time has many definitions per se, but the basic idea being it's "the measurement of change" so as we know, all matter looses it's ability of changing with the loss of kinetic energy. and the where it ...
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33 views

Thermal Equilibrium of two thin sheets

While reading Gibbs' Elementary Principles in Statistical Mechanics I came across this footnote: The most simple test of the equality of temperature of two bodies is that they remain in ...
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1answer
61 views

Pressure, density, volume and mass in a room

Here's the question. A window in the room is open. The next day, the temperature of the room has increased, but the pressure of the air stayed the same. State and explain what has happened to ...
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1answer
94 views

Highest temperature possible to achieve using magnifying glass and sunlight [duplicate]

Temperature of the surface of the sun is about 5750K. Can you heat an object to more than 6000K using magnifying glass and sunlight? According to second law heat cannot be transferred from colder to ...
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1answer
35 views

Temperature effects on lead against radiation

I would like to know if bringing lead to near absolute zero temperatures would have any affects on how resistive it is against gamma radiation. It takes 40 centimeters of lead to reduce gamma ...
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1answer
70 views

Question about ohmic conductors

I'm having some trouble understanding Ohm's law. My trouble is with the different ways it is described when referring to ohmic and non-ohmic conductors. If someone can answer this question I think it ...