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What is absolute temperature? 
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#1
Dec404, 09:15 PM

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What is absolute temperature? The aboslute value of a temperture value?



#2
Dec404, 09:31 PM

P: n/a

Not sure in what context you are asking the questions but possible answers are :
1. The temperature in degrees Kelvin (vs C or F) 2. A number that is proportional to the thermal energy of a substance 3. (?) 


#3
Dec404, 09:40 PM

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I think its the first one, though it could go either way.



#4
Dec504, 09:38 AM

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What is absolute temperature?
Ok, the first thing you got to know is that "absolute temperature" exactly means "temperature in degrees K (Kelvin)".



#5
Dec504, 10:13 AM

P: 297

The absolute temperature scale is in Kelvin as others have said. On this scale, 0 K is the coldest anything can ever get. It's the same scale as celcius (centigrade) except you have to add 273.
So if it is 61 F in your garden, that's about 16 C or 289 K 


#6
Dec504, 02:20 PM

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PF Gold
P: 11,155

The Absolute scale can be defined by any two points, say 0K (where all classically calculated molecular motion stops) and 273K (where water freezes at 1 atm) and a linear interpolation/extrapolation. 


#7
Dec504, 06:02 PM

P: n/a

For the sake of completeness, space can also contain thermal energy, even though it is not a "substance", and so that is how it can be said that interstellar space (background radiation) is at about 23 K. If I understand correctly, this energy is basically all in photon (microwave) form.



#8
Dec604, 06:07 AM

Sci Advisor
PF Gold
P: 1,479

As others have said, Absolute or Thermodynamic Temperature is measured in Kelvin scale. If you want a definition, apart of that given by the Kinetic Theory, you may as well take a look at the First Principle:
[tex] dU=TdSPdV[/tex] So that: [tex] T=\frac{\partial U}{\partial S}\Big)_{V} [/tex] Now is when a physicist should tell us if this derivative can be negative or not. I don't really know. 


#9
Dec604, 06:44 AM

P: 4,006

The conditions for this to occur are for example that the spinspin relaxation time is little compared to the spin lattice relaxation time. This means that the spins mutually interact long before thermal degrees of freedom come into play... regards marlon 


#10
Dec604, 06:59 AM

Sci Advisor
PF Gold
P: 1,479

For engineers, it would be a funny thing to design and test such device... 


#11
Dec604, 07:05 AM

P: 119

Temperature can be defined with reference to the propeties of some standard substance. Like, in terms of expansion of mercury as in the ordinary thermometer, expansion of some gas, resistance of a metal.
But then, there is another way in which one can define temperature. In terms of kinetic energy of the gas molecules. When defined in this way, the temperature is said to be the absolute temperature as it doesn't depend upon some other reference. spacetime www.geocities.com/physics_all 


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