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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How the mechanical equivalent of heat is employed in this situation?

Reading a little about the "mechanical equivalent of heat" what I understood is that we can convert units between calorie and $J$ by setting $$1\mathrm{\ J} =4.1860 \mathrm{ \ cal}.$$ Now, I saw a ...
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35 views

Gas/liquid pressure equilibrium of water in an exotic environments

So I'll preface this by saying this is not some evil homework assignment, this came about from some idle talk of colonizing the moon by a couple of software engineers when we realized we had no idea ...
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30 views

Emissivity and Final Temperature of a Black and White object

Objects can be categorized as blackbodies (emissivity $\epsilon = 1$), grey bodies (emissivity $\epsilon < 1$) and white bodies (emissivity $\epsilon = 0$). If we placed two objects (identical ...
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195 views

Chemical Potential as a function of Temperature

I have considered an ideal fermi gas. Then, we can obtain an expression for chemical potential as a function of Temperature. I want to understand the physical significance to it or what it really ...
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7 views

Temperature dependence of phase transition in Quantum Hall Effect

Most phase transitions have a distinct critical temperature, depending on the parameters of the system. For example, the critical temperature of Bose-Einstein condensation depends on the particle ...
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4answers
484 views

What is temperature?

Recently I read an interesting article about negative temperature. I was puzzled because I thought before that temperature has definite meaning in thermodynamics: it tells about how fast atoms jiggle. ...
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72 views

Might the zero point of the Kelvin scale been mislocated? [closed]

This is fundamentally a thermodynamics question, but it has ties to cosmology and the temperature of the cosmic microwave background (cmb). Since T(cmb) ~ 2.725 K it brings up a comparison with the ...
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1answer
21 views

Heat capacity at constant volume and internal energy

I read that heat supplied at constant volume to a system containing ideal gas changes the internal energy of system, i.e $q=nC_v\Delta T=\delta U$ But what happens if I heat a system and change its ...
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32 views

Meaning of $\frac{1}{\beta} \frac{\partial \ln{Z}}{\partial X}$ in arbitrary ensembles with X being a sharp Observable of the System

I often find the statement, that for an arbitrary ensemble with Observables $O_i$ of which only the mean value is known, and $\tilde{O}_j$ that are known exactly, the partition function ...
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31 views

What do you call a kiln/furnace which can melt iron? [closed]

I need a small kiln/oven/furnace to melt 100 gram (4oz) of iron. Iron melts at 1538°C Googling it bring only low temperature kilns or multi-ton industrial furnaces. But there must be something ...
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Rate of Temperature Change in Air to Air Contact

What is the rate of temperature change when it is x Liters of air to x Liters of air at two different temperatures directly contacting each other? I need to know this for a hypothetical telekinesis ...
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The temperature of photon and its energy

Do photons have temperature? If not, does it mean that photon lose energy while travelling through space? As the planets farther away from the sun are comparatively cooler than the one that are ...
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42 views

Conterflow heat exchanger with different flow rates

If we have tube in tube heat exchanger, in classic situation surface area in contact with both fluids is the same (if we ignore wall thickness of the tube). If fluids have significantly different ...
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43 views

How accurate is the following description (quoted) of what happens when a liquid is heated in a closed vessel?

"Boiling does not occur when liquid is heated in a closed vessel. On heating continuously vapour pressure increases. At first a boundary is visible between the liquid and vapour phases because ...
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50 views

What is the difference between thermodynamic and empirical temperature?

When I've studied Thermodynamics I did so in Callen's book and there the author talks about temperature as a single thing, which mathematically is simply defined as: $$T = \dfrac{\partial U}{\partial ...
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50 views

Does temperature affect to movement of electrons?

Does temperature affect to the movement of the electrons circulating the core of an atom? Do they move faster if temperature increases?
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67 views

The temperature of an electron

Does an electron have a temperature, if so, what is it? Imagine an electron (Ke = 1 eV) in a tube at room temperature (300 K) what is its temperature? Imagine now same electron in space (3 K) ...
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29 views

Temperature reading [closed]

A cup of coffee at 85 degree centigrade is placed in a freezer at 0 degree centigrade. The temperature of the coffee decreases exponentially so that after 5 minutes it is 30 degree centigrade. What ...
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1answer
59 views

Does gold hold heat [closed]

If you held a torch to a piece of gold then pulled it away would the gold be hot to the touch?
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2answers
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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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2answers
155 views

Why aren't the hottest stars mostly invisible due to radiating mostly in ultra-violet? [duplicate]

The hottest stars have surface temperatures in the range of 40,000K. Wolfram Alpha says that such a star acting as a black body should radiate almost no energy in the visible spectrum. Why then do ...
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49 views

Does solar eclipse have impact over increase of earth's temperature?

Does a solar eclipse have an impact on global temperature? Wired theory : When I jump, does the Earth recoil? Yes, the Earth has to move in some way for momentum to be conserved. However, since ...
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5answers
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Why does a larger thermal conductivity provide a smaller temperature gradient?

I was thinking about Fourier's Law in heat transfer today and for some reason I am just not understanding the relationships it gives us. Fourier's tells us that if the heat transfer rate is kept ...
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1answer
79 views

Help me solve a heat conduction/emission transfer problem. Mathematica has failed me

My problem: A thin-walled tube (length $L$, diameter $D$ and wall thickness $t \ll D$) is in a vacuum. It is held on one end (at $x=0$) by a heat source at constant temperature $T(0)=T_0$. The only ...
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24 views

Calculating Effects of Added Insulation on Rate of Temperature Change

I have recently begun tracking the temperature data available from my Nest thermostat. Among other things, the hope is to use this data to measure the effectiveness of additional insulation and other ...
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1answer
29 views

Coefficient of Linear Expansion (Formula)

Quoting directly from my textbook: We define average coefficent of linear expansion in the temperature range $\Delta T$ as: $$ \bar \alpha = \frac 1L \frac{\Delta L}{\Delta T} $$ The ...
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Restoration of spontaneously broken symmetry at high energy

It is common to find books saying that above a certain energy, a certain symmetry in particle physics is restored, e.g. the $SU(2)\times U(1)$ electroweak symmetry was unbroken between $10^{-36}$ to ...
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Does invariant mass depends of temperature? [duplicate]

From special relativity theorie we know that $E = mc^2$. When a system acquires energy, mass becomes greater. That is clear for kinetic energy, because we have a formula that gives m as a function of ...
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How loud is the thermal motion of air molecules?

In other words, given a magical room with walls that produce no vibration and transmit zero vibration from the outside, and nothing on the inside except room temperature air, what would be the noise ...
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5answers
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Does decrease in temperature affect mass $E=mc^2$?

My understanding of Quantum physics and String Theory is very basic and I don't yet have a grasp on the maths, but in my research I have come up with a question. Does a decrease in temperature also ...
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8answers
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Will a hole cut into a metal disk expand or shrink when the disc is heated?

Suppose you take a metal disc and cut a small, circular hole in the center. When you heat the whole thing, will the hole's diameter increase or decrease? and why?
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Is it possible for a crystal to have different structures at different temperatures?

For instance, suppose it is a 50-50 alloy of two metals that is BCC at room temperature $T_0$. If I raise (or lower) the temperature, is it possible for the bonds in the crystal to rearrange and form ...
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27 views

How to determine how much AC current is needed to heat a piece of copper wire to a specific temperature?

I would like to verify some test equipment that I have setup, but I haven't found a good mathematical model to do so. I believe, based on some fast response temperature probe data, that I'm reaching a ...
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1answer
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What is the relation of particle velocity, temperature, and reaction activation energy

So, this curiosity has arisen for a fun project I thought I'd tackle, where I'm attempting create a crude simulation of an internal combustion cylinder. I wanted to explore the particle level ...
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Constant Temperature Cooling

In my thermodynamics textbook there is part of a question that seems to be a contradiction. ...Superheated refrigerant R-134a at 20 C, 0.5 MPa is cooled in a piston/cylinder arrangement at constant ...
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Computing Maximum Heat Capacity

I've encountered a problem in my statistical mechanics class that I'm not sure I'm approaching correctly: Consider a system of N interacting spins. At low temperatures, the interactions ensure that ...
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147 views

How much energy would be required to make one tea cup full of Earl Gray tea at 100F?

On the TV show "Star Trek: The Next Generation", Captain Picard is often pictured using a replicator to materialize a cup of "Earl Gray tea, hot". Besides wondering what they do with all the empty ...
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Thermistor is more sensitive than metals [closed]

Can anybody tell me, why a thermistor is much more sensitive at temperature variation than a metal?
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23 views

Determine the temperature of a solar cell

Is there a formula regarding solar cells that includes the temperature as a factor that can be used to evaluate its current amount of thermal energy given you have every other variable and factor? ...
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28 views

Windchill effect or something else

If I'm driving a fire truck on a cold winter night, given the following factors. Will it create an effect that could freeze the water pump faster than if it were just parked in the same conditions. ...
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214 views

Temperature rise during friction

Why does the temperature increase when the load increases during friction? Why does the temperature increase when the contact time increases during friction?
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45 views

Heat, temperature and entropy

I have many questions concerning this topic. I know that temperature measures the tendency of an object to give up its internal energy. The transit of internal energy is called heat. I don't know if ...
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41 views

Pressure Volume graphs and work done

So if I have a system where pressure, volume, and temperature change, how do I find the work done on the system? I look at an example where you simply use $\mathrm{d}W =-p\, \mathrm{d}V$, but I ...
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290 views

Local temperature equation for a planet

After seeing in science fiction too many planets with two suns that look too much like a geocentric system, I'm trying for my own amusement to understand if it's really possible to have a planet with ...
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2answers
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Can we enhance a thermal gradient by combining a dark surface and a shiny surface with an external glass layer?

I refer to the article at this site: http://solarcooking.wikia.com/wiki/Solar_Kettle-Thermos_Flask As we know, dark surfaces absorb radiation (eg. solar water heater), while shiny surfaces reflect ...
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Does hot air really rise?

"Heat rises" or "warm air rises" is a widely used phrase (and widely accepted phenomenon). Does hot air really rise? Or is it simply displaced by colder (denser) air pulled down by gravity?
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Determination of temperature from electromagnetic emissions

The actual measured radiation intensity at different frequencies varies significantly from the ideal theoretical Planck curve. For example, here is the result of a typical laboratory measurement at ...
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Did the universe have a temperature during inflation?

I've heard it said that inflation was not an equilibrium process. But I've also heard it said that during inflation, the temperature of the universe was much cooler than before or after. If the ...
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3answers
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Temperature behavior over time of black or white cars in hot, sunny regions

How does the color of a car influence its inner temperature change over time when parked outside in windless, hot and sunny regions? I know what's the common idea about that: black cars are supposed ...
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Is the formula of temperature $ \frac{1}{T}= \left(\frac{\partial S}{\partial U}\right)_{V,N}$ applicable to all type of ensembles?

I have seen multiple posts on this page that explained the statistical definition of Temperature as the derivative of the Entropy to the energy: \begin{equation} \frac{1}{T}\equiv ...