Is the Net Work Done Positive and Does It Function as a Heat Engine?

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SUMMARY

The discussion centers on a thermodynamic cycle involving 2 moles of gas transitioning through states A, B, and C. The net work done during the complete cycle is positive, as the work performed by the gas from state A to B exceeds the work done on the gas from state C to A. Additionally, the device functions as a heat engine because the system's heat increases and the net work is positive, contrasting with the characteristics of a refrigerator where more work is required to transfer heat from a cold to a hot region.

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Homework Statement


A cylinder contains 2 moles of gas initially at state A it has a volume of 1*10^-2m^3 and a pressure of 4*10^5. It the is brought isobarically to state B where the new volume is 2*10^-2. It is then brought at a constant volume to state C where the temperature is the same as in step A. It is then finally brought isothermally back to state A.
a)Is the net work done during the complete cycle positive, negative, or zero?
b)Is this device a heat engine or a refrigerator?


Homework Equations


Work=p(V2-V1)



The Attempt at a Solution


I've already got answers but I'm not positive.

Part a
Positive b/c the work done by the gas going from A to B is greater than the work done on the gas going from C to A. This is seen through A bring at a higher pressure than C while they have the same differential in volume. No work is done from B to C.

Part b
I said it is a heat engine for two reasons. First the heat of the system increases and second b/c the work done during the cycle is positive. In a refrigerator work more work must be done on the system for the cold air to move to the hot region.
 
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Everything seems to check out here.

You should probably make a P-V graph if you want to show your answers better.
 

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