(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

21. A heat engine operates in a cycle between temperatures 700 K and 400 K. The heat input to the engine during each cycle is 2800 J. What is the maximum possible work done by the engine in each cycle?

(A) 1200 J

(B) 1600 J

(C) 2100 J

(D) 2800 J

(E) 4400 J

I believe that the answer is E. I just don't know how to prove it. If you could show that would be great. I know that

2. Relevant equations

e = |W|/|Qh|

|Qh| = |W| + |Ql|

e = 1 - |Ql|/|Qh|

3. The attempt at a solution

I'm lost...

e = |W|/|Qh|

|Qh| = |W| + |Ql|

e = 1 - |Ql|/|Qh|

I don't remember how to do this type of problem...

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# Homework Help: Heat Engine Cycle Question

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