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 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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61 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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91 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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36 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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1answer
25 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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2answers
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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213 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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32 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
36 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
65 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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Is Moon too hot?

I find it puzzling that Moon's maximum "daily" equatorial temperature is almost 400K. Earth's theoretical black body temperature would be 279K at 1AU, and Moon is the same distance from Sun, yet its ...
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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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30 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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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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25 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
31 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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53 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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70 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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33 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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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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44 views

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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11 views

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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44 views

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 \left(\frac{\...
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297 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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87 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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68 views

Can we determine the surface temperature of stars other than the sun by using the black body radiation theory?

It is well known that the surface temperature of the sun can be determined by fitting the solar spectrum to the black body radiation spectrum. Is this scheme feasible for other stars? Possibly the ...
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234 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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60 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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96 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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1answer
15 views

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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137 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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117 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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50 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 "Namu")...
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1answer
133 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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141 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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42 views

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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113 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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104 views

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 ...
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124 views

Can I cook an egg by holding it in thermosphere?

It is known that in thermosphere, air temperature is rising sharply with increase of altitude. In upper atmosphere, temperatures can even reach 2000°C or higher: see 2. However, air there is ...
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Does a rapid temperature change crack annealed glass [closed]

Over at Lifehacks.SE there is a question about how to remove ice from a windshield. One answer suggests using water but warns that using boiling water might crack the windshield. As far as I ...
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Hotter than the Absolute Hot?

Is the Planck temperature ($1.416×10^{32}$ kelvin), the hottest possible temperature that can ever be reached, with absolute zero as it's opposite analogue ? All I know is a particle with that ...
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Why do some materials shrink when their temperature increases?

In my vision it would seem quite logical that all materials expand when temperature rises. Because the particles get more energy and travel larger distances when moving. But apparently there are ...
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82 views

Can temperature rise after sunset?

Generally speaking I suppose temperature rises as long as the sun is up and then it continues to fall until sunrise the next day. I have once noticed temperature rise temporarily during night (In my ...
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49 views

Large scale structure of the universe

I have read of two seemingly straightforward explanations that give reasons for the inhomogeneity of the large-scale structure of the universe (i.e. why stars / galaxies formed where they did) One is ...
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3answers
63 views

The temperature a liquid would boil: question incorrectly formulated or not?

I have met a question in a high school physics book which I think is incorrectly formulated. The question is this: In order to reach boiling temperature, a certain liquid requires twice the amount of ...
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Hottest period in the history of the universe

Stack exchange's tagline is 'hot questions' - so here is one that will hopefully cause some heated debate. I remember hearing that the period immediately after inflation is theorized to be the ...
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75 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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3answers
116 views

Would a bag of neutrons have temperature?

Neutrons interact with each other only via exchange interaction, while "every-day particles" and their temperatures are governed by electrostatic forces. What are the implications of this difference ...
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My bathroom door stays open in summer [closed]

My bathroom door remains open in summer, but in the winter it stays about halfway between fully open (90 degree angle, against a window) and closed. The door is between bedroom and bathroom and it is ...
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How are melting points of metals measured?

How are melting points of metals measured? What apparatuses are used and how do they "conceive" heat units?