How do I find the work done in an adiabatic process?

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Ruby_338
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How come ##adiabatic \,work = C_v(T_2 -T_1)##
 
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If the transformation is adiabatic you have that ##\Delta U=-W## for the second law of thermodynamics because ##Q=0##. So ##W=-\Delta U = n\cdot C_{v}(T_{1} -T_{2})## where ## C_{v}## is the specific heat for constant volume and ##n## represents the mole. It is strange that in your formula there isn't ##n##...

Ssnow
 
Ssnow said:
If the transformation is adiabatic you have that ##\Delta U=-W## for the second law of thermodynamics because ##Q=0##. So ##W=-\Delta U = n\cdot C_{v}(T_{1} -T_{2})## where ## C_{v}## is the specific heat for constant volume and ##n## represents the mole. It is strange that in your formula there isn't ##n##...

Ssnow
Maybe he means "per mole" or "per unit mass.". Also, irrespective of the 2nd law, Q is equal to zero for an adiabatic process.
 
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I forgot to add the n. How did we get ## - \Delta U = n C_v (T_2-T_1) ## ?

Can you show me step by step?
 
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Isn't it straightforward? How is [itex]C_v[/itex] defined? What is [itex]nC_v\Delta T[/itex]?
 
Then start by checking. Per forum rules you should do your legwork, not ask others to do that for you.
 
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Okay. Ill remember that