Author Topic: Physics Question.  (Read 1156 times)

Offline pikutata

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Physics Question.
« on: August 30, 2009, 05:02:58 am »
hi,

the kinetic theory of gases leads to the equation

1/2m<c^2>=3/2kT.

mind explaining to me the significance of the quantity 1/2m<c^2>?

and using the equation to suggest what is meant by the absolute zero of temperature.

ps: this is past year questions for CIE PHYSICS A2 may/june 2002. paper 9704/4. question 3.

Offline abdullahnisar2005

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Re: Physics Question.
« Reply #1 on: September 18, 2009, 09:47:03 am »
see paper mark scheme

Offline astarmathsandphysics

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Re: Physics Question.
« Reply #2 on: September 18, 2009, 11:54:43 am »
hi,

the kinetic theory of gases leads to the equation

1/2m<c^2>=3/2kT.

mind explaining to me the significance of the quantity 1/2m<c^2>?

and using the equation to suggest what is meant by the absolute zero of temperature.

ps: this is past year questions for CIE PHYSICS A2 may/june 2002. paper 9704/4. question 3.

1/2m<c^2> is the average kinetic energy of the gas molecules
If this energy is zero then the left hand side is zero, so the right hand side must be zero, which can only happen if T=0, ie absolute zero since it is not possible for the left hand side to be less than zero.