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## Homework Statement

A Carnot engine runs between a high temperature of 500 C and a low temperature of 50 C. The isothermal expansion (upper branch) occurs between a volume of 0.5L and 1.0L. The isothermal contraction (lower branch) occurs between 2.0L and 1.0L. There are 2 moles of gas involved. Calculate the work done by the engine, the heat taken in, and the heat ejected. calculate the efficiency o the cycle. Draw a PV diagram and show the area corresponding to the total work being done. Show the beginning and end points of the isothermal and adiabatic curves. Show during which branch of the cycle heat enters and leaves the engine.

## The Attempt at a Solution

So why does Q

_{H}= -W, but it also equals Q

_{C}+ W ?

And W=e*Q

_{H}? With e = efficiency

Hmm. Ok so when I typed that, something sparked. So I said QH is = to W. But then I actually calculated the work for my answer based off of QH*e. I just calculated the work for the lower branch and it came out to equal Q

_{C}.

So how can I make sure not to confuse myself I guess? The heat entering the system is work being done on the system and work leaving is work being done BY the system? So then I can find the total work of the system which may or may not be positive?

Why doesn't the total W=e*Q

_{C}?

Thanks for the help