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 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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If you stop water from expanding, will its temperature stop rising?

Water expands when it heats up. If you heat water in a container that prevents it from expanding, will its temperature top out -- maybe around the boiling point? And if not, will it still turn to ...
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simulations at constant pressure-volume and constant volume-temperature

I have read some papers where the authors perform simulations at constant pressure and constant volumen or sometimes constant volume constant temperature. My question is when is it better to use one ...
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Could the contents of a bottle affect the surface temperature of that bottle?

e.g. If I had two bottles one with Vodka in and one with Water in (both the same glass bottle spec/size) If I then put these two bottles in a freezer would the surface temperature of the bottle be ...
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How did the radiative flux of each gas giant planet change with respect to time (since their formation)?

We know that each gas giant planet was warmest when it was young. This warmth came from internal heating from both radioactive decay and from gravitational potential energy. This warmth, in turn, ...
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818 views

Calculate time to heat my swimming pool

I have a swimming pool of 5300Liters. I have a heating element from a washing machine taking 1min17s to heat a bucket (10L) of water from 22 degrees to 30 degrees celcius. the water in my pool is 19 ...
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Heat in the car during sunny day

Why is it hotter inside an isolated car (air conditioning is off) than outside during a sunny day in summer?
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Why does the gas get cold when I spray it?

When you spray gas from a compressed spray, the gas gets very cold, even though, the compressed spray is in the room temperature. I think, when it goes from high pressure to lower one, it gets cold, ...
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How can it be that the beginning universe had a high temperature and a low entropy at the same time?

The Big Bang theory assumes that our universe started from a very/infinitely dense and extremely/infinitely hot state. But on the other side, it is often claimed that our universe must have been ...
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Effect of temperature on radioactivity?

I'm researching the effect of temperature on uranium radioactivity, however I can't find any solid empirical evidence to prove the notion that temperature does not affect radioactivity. Can anyone ...
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Why would colder air disperse condensation on a car windshield?

The outside temperature was somewhere between the hot and cold that blows on the inside through the car's vents. I know the condensate is on my side because I can reach forward and write on it with my ...
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Can temperature be defined as propensity to transmit thermal energy?

I was recently surprised to learn that defining temperature isn't easy. For a long time, it was defined operationally: how much does a thermometer expand. Also surprising, temperature isn't a ...
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Does tea stay hotter with the milk in it?

A little thought experiment, similar to this one: Imagine you are making a cup of tea when the door bell rings. You've poured the boiling water into a cup with a teabag in it. As you're just about to ...
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396 views

Using heat energy to increase temperature

It's been a long time since I studied thermodynamics in college years ago, but I was just wondering this: I know that a large bathtub of 10 C water has more heat energy than a small cup of 20 C ...
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heater in a perfectly insulated box

Imagine a perfectly insulated box, placed inside the box is an electric heater. The heater is switched on and the box is left to reach equilibrium with its surroundings. What is the final temperature ...
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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 there a timeline in urban area night temperature?

Fact: We all know that during the day concrete absorbs heat and releases it during the night, making urban areas hotter than rural areas. I observed that after sunset the ambient temperature is going ...
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381 views

Understanding Heat

Heat or thermal energy as understood is nothing but motion of molecules of the matter. If the molecules are tightly bound (in case of solids), it is to-and-fro molecular vibrations, otherwise it is ...
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Hail stones in summer?

This has always puzzled me. Yesterday (in London) it started hailing despite it being about $20^oC$. A couple of years ago I experienced hail in Sicily when it was about $35^oC$ in the shade!. How is ...
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In summer are the upper storey flats more hot or the lower storey flats?

I have often heard neighbours talking things like in a multi storied apartment, the upper flats are more hot in summer then lower flats (or vice versa?) and similarly for some comparison in winter? ...
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How can I calculate how long to keep my beverage chilled?

The problem is simple, I suppose... I have a beverage at room temperature (let's say 23°C) in an aluminum can (it's a Barq's root beer.) I want to put it in a freezer (let's say it's at -17°C). How ...
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what cools bottle of water faster: ice or snow

Imagine you have a pile of snow and a pile of ice shards. You put a soda bottle which has a room temperature into both piles. Which bottle is going to cool down faster?
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Significance of letters in Hertzsprung-Russell (H-R) diagram

The Hertzsprung-Russell diagram that categorizes star types uses the letter codes O, B, A, F, G, K, and M to indicate a star's temperature/color. Hottest (blue) is O and coolest (red) is M. What do ...
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Why does a thermometer in wind not show a lower temperature than one shielded from it?

I'm a little familiar with the physics and thermodynamics of the wind chill effect, but this question seems to come up from time to time: Why, given two temperature sensors or thermometers in the ...
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How does water evaporate if it doesn't boil?

When the sun is out after a rain, I can see what appears to be steam rising off a wooden bridge nearby. I'm pretty sure this is water turning into a gas. However, I thought water had to reach 100 ...
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What are the temperatures of objects in Low Earth Orbit (LEO)?

What is the temperature of objects in Low Earth Orbit? Consider LEO to be 600km to 800km.
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How does my air-cooling unit work?

During the winter, my office gets a little cold. I have a unit (essentially a space heater) that heats the area around it to help keep me warm. Now that it's summer, I realize the unit also has a ...
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What effect would liquid air have on a resonant coil?

This description of Tesla's "magnifying transmitter", which supposedly used electrical resonance to transmit energy (similar to resonant inductive coupling?) states that the coils (or at least part of ...
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Heat reflection on distant planets

I was watching a documentary last night on the first planet discovered outside our solar system. The first one apparently is a giant gas planet that orbits very close to its sun over a very fast ...
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What exactly is heat?

Is it energy? Is it energy per unit volume? Is it energy per unit time i.e power? What is it?
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Why does the air we blow/exhale out from our mouths change from hot to cold depending on the size of the opening we make with our mouth?

Why does the air we blow/exhale out from our mouths change from hot to cold depending on the size of the opening we make with our mouth? It's not just a subtle difference, but significant in my ...
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How much power to keep surface of aluminum plate at given temperature?

I want to heat one side of an aluminum plate enough to hold the other side of that plate $100K$ above ambient. I'm willing to assume that the heated side of the plate is "well" insulated (along with ...
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What is the effect of temperature on electrostatic-gravitational balance?

We have two identical massive metal spheres at the same temperature at rest in free space. Both have an identical charge and the Coulomb force [plus the black-body radiation pressure if the ...
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Best way to keep food cool indoors without using a fridge/freezer

I've just moved into my first place, and for reasons I do not condone or recommend I don't have any method of refrigeration right now. Luckily I now live very close to shops, so it isn't a big deal, ...
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Glass melting at near absolute zero?

I read this report and summarise here but my question is - if quantum mechanics will make glass melt at temperatures near absolute zero and it is near absolute zero then wouldn't this be a huge issue ...
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Light emitted by an object according to its temperature

According to this picture the light emitted by an object depends on its temperature. That makes perfect sense when we heat a metal. As its temperature raises we see it red at first, then orange, ...
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How should 500ml water bottles be stored in the fridge so they will be coldest?

Should they be taken out of the wrapping and stored as single units, or should I leave them in the package? EDIT to add I mean, the package is 24 bottles bundled together. Should I just leave them ...
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How can I calculate Vapor Pressure Deficit from Temperature and Relative Humidity?

I have a series of measurements of temperature and relative humidity (RH), together with mosquito capture data. Because mosquitoes are sensitive to desiccation, it's reasonable that RH may be useful ...
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Temperature of a System of molecules

Suppose I have a closed system with N molecules in it which are vibrating and all motion equations (rotation, translation and vibration) of the system are known along with any EM field equations in ...
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What is planetary surface temperature given constant sub-surface temperature?

If a planet of radius R1 has a constant sub-surface temperature T0 at R0 < R1, what is the long-term equilibrium surface temperature T1? Say we assume constant thermal diffusivity of the planet ...
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Is there an equation for convective heat transfer?

Is there an equation I can use to calculate the temperature (as a function of time) of an object which is gaining or losing heat by convection? Or equivalently, the rate of energy transfer from the ...
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Is temperature in vacuum zero?

From Wikipedia entry on Kinetic Theory The temperature of an ideal monatomic gas is a measure of the average kinetic energy of its atoms. Now if I remove all the particles from the box shown ...
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Approximating mean daily and hourly temperature beyond Fourier series

Summary: What "well-known" and short parametrized mathematical function describes daily and hourly temperature for a given location? If you look at the mean daily temperature graph for a given ...
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Computing delta temperature based on radiation and heat loss

Is there a formula that gives me the instantaneous change in temperature under ideal circumstances? Details: On a cloudless day, temperature is affected by two major things(?): While the Sun is ...
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159 views

Does a towel that's spread out cool faster than one that isn't?

I was thinking about how they say those sails on top of some dinosaurs helped regulate their body temperature. If a dinosaur didn't have that sail, would it really make any difference? If you heated ...
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Why is there no absolute maximum temperature?

If temperature makes particles vibrate faster, and movement is limited by the speed of light, then temperature must be limited as well I would assume. Why there is no limits?
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Why doesn't air freeze?

I am in no way experienced in the Physics field so this question may seem a bit silly but i'd appreciate an answer :) Why doesn't air freeze?
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Why do frozen objects have a higher propensity to snap/break cleanly than non-frozen/warmer ones?

Why do frozen objects have a higher propensity to snap/break cleanly than non-frozen/warmer ones?
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What’s the relationship between thermal radiation and Johnson thermal noise?

All objects above absolute zero emit radiation due to random collisions between the atoms they are made of. The spectrum of radiation emitted varies according to the temperature of the object, I ...
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What does it mean a temperature of billions of degrees?

I read a few days ago that in the LHC temperatures of billions of degrees were achieved. I'm curious to know what does it really mean such a temperature? The concept of temperature is easy to grasp ...