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Homework Statement
In the problem, we were to derive work and heat for each leg of the cycle. Then we are asked:
In the definition of the efficiency of this cycle, η =W Qpos , where Qpos is the total positive heat flow to the engine, what is the efficiency of the cycle when Th = 700K and
Tc = 400K? V1 = 0.5 L and V2 = 1.5 L. Compare this efficiency to the efficiency of a Carnot cycle that operates between the same temperature extremes.
Homework Equations
Work = integral from Vi to Vf of PdV
W done during cycle = nr(Th-Tc)ln(vf/vi) Derivation here:
http://www.pha.jhu.edu/~broholm/l39/node5.html
Q = Cv(Th -Tc) - nRT ln (Vf/Vi)
We are told Cv = 5/2 * R
efficiency of a carnot cycle = 1- Tc/Th
The Attempt at a Solution
I have attempted to get the solution but have come up with a result that is about an order of magnitude too small that i am unable to rectify. It is part c in the attachment.
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