## Adiabatic Process: which is constant?

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Penemonie
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### Adiabatic Process: which is constant?

Question #21 on the official GRE Physics Prep book: For an adiabatic process involving an ideal gas having volume V and temperature T , which of the following is constant? ( γ = CP/CV ) The answer is T*V^γ-1.

According to this website: http://hyperphysics.phy-astr.gsu.edu/hb ... adiab.html, P*V is constant but not with T. So what is the derivation? Can I get the answer from PV=nRT?  bunnysid
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### Re: Adiabatic Process: which is constant?

For an adiabatic process PV^γ = constant. Now use PV=nRT to find P in terms of T and put it in the equation. You will get the answer straight away.

throwawayhehexD
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