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 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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83 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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31 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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195 views

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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85 views

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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31 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
33 views

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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1answer
60 views

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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29 views

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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2answers
234 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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31 views

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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24 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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1answer
30 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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238 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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48 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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56 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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291 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
31 views

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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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 ...
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Maximum temperature [duplicate]

If atoms in a region are still, temperature is at the minimum: 0K. However, given that the speed of the movement of atoms, or their rotation, cannot exceed c, is there a maximum temperature? ...
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1answer
64 views

Can two different objects or system of molecules have different temperatures, but having same internal kinetic energy?

If I take an extreme case, where a body has only an internal potential energy with zero internal kinetic energy, does this body have a temperature? Another question related to it: if two objects A and ...
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201 views

How do we define temperature?

I was watching this video What is Temperature?. It states that when we measure temperature we are measuring $dU\over dS$ at equilibrium. But at equilibrium, how the entropy and the internal energy are ...
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49 views

How quickly does the temperature rise in a water container submerged in a hot water bath?

Let's assume I have a small bottle (neglecting any insulation from the walls of the bottle) containing e.g. 150ml water at 4°C and place it in a larger pot with sufficient water at 80°C so that the ...
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1answer
90 views

Is climate change caused by humans? [closed]

Some people argue it is not because it is caused by solar cycles (sometimes the sun brights more than others thus increasing the Earth's temperature) and that the energy that $CO_2$ traps isn't enough ...
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Acer saccharum (Sugar Maple) Sap & Freezing

This may or may not be the appropriate scientific discipline to ask this question of, but I'll give it a shot. I'll happily invite chemists to chime in as well. It's time to tap sugar maples in the ...
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1answer
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Motivation for integrals over scalar field

I'm looking for good examples of physical motivation for integrals over scalar field. Here is an example I've seen: If you want to know the final temperature of an object that travels through a ...
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70 views

CFT and temperature

I have tried to think about this for some time but could not really go anywhere. Sorry for the sloppy question and thanks for any pointer. My question is about CFT at finite temperature and ...
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116 views

The impatient hot tub owner [closed]

An impatient man owns a 300 gallon hot tub. He comes home from a hard day of work and sees that his hot tub is currently simmering at 90F. For maximum relaxation, he wants it at 104F. However, the hot ...
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103 views

Does shaking a kettle whilst boiling increase the temperature faster than a statically-placed jug?

Water molecules move faster at higher temperatures. Does shaking a boiling kettle whilst it is in the process of boiling water increase the rate of rising temperature ? Is it worthwhile to do so ...
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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
49 views

Can this Temperature Scale be Considered an absolute temperature scale?

Me and My friend are having a discussion about Absolute Temperature Scales. I think Absolute Temperature Scales are those who have their zero on Absolute zero. So Can we define a new Scale (say ...
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1answer
129 views

Number theoretic loophole allows alternative definition of entropy?

A bit about the post I apologize for the title. I know it sounds crazy but I could not think of an alternative one which was relevant. I know this is "wild idea" but please read the entire post. ...
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1answer
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Why is the logarithm of the number of all possible states of a system differentiable?

Temperature of a system is defined as $$\left( \frac{\partial \ln(\Omega)}{ \partial E} \right)_{N, X_i} = \frac{1}{kT}$$ Where $\Omega$ is the number of all accessible states (ways) for the system. $ ...
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439 views

Why can we hear sound better on the water than on land?

If we sit in a boat on a lake we can often hear people talking on the shore clearly in contrast to sitting in an empty field and hearing the people talk over the same distance. I heard that this ...
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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
107 views

Does temperature have any effect on static electricity?

This is one of those questions that came up during a discussion with a friend on static electricity. His argument (which I dispute) is that there must be a relation between temperature and the ...
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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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Could temperature have been defined as $-\partial S/\partial U$?

When coming up with a definition of temperature, it's typical to start with an empirical definition that a system with a hotter temperature tends to lose heat to a system with a colder temperature. ...
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111 views

Shouldn't General Relativity Predict a Maximum Temperature?

I've seen a lot of questions about maximum temperature and “absolute hot” — several ask if special relativity places any limits on temperature (clearly not). (Also this discussion of absolute hot on a ...
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Why can't we use Boltzmann's ideal gas law using temperature in Celsius (intuition)? [closed]

Mathematically, i can see why we won't get the same results when inserting a temperature in Celsius rather than Kelvin(because K=C+273.15), but i can't understand how can a law not "work" for any man ...
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Differences between thermal and non-thermal plasmas

I have a doubt about plasmas which may as well be trivial or very stupid, but I couldn't get a clear and straightforward answer anywhere I looked, and I can't get the grasp of it since I wasn't given ...