How much work is done by the engine?

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SUMMARY

The discussion focuses on calculating the work done by an engine with a heat input of 1330 J/s and a heat output of 800 J/s. Using the efficiency formula \(QL/QH = 1 - e\), the work done (W) is determined to be 1065 J. The calculations reveal that the engine's efficiency (e) is 0.40, leading to a heat rejected (QL) of 1.6 kW. The conservation of energy principle is applied, confirming that the heat input equals the sum of work done and heat rejected.

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Homework Statement


Heat input of an engine is 1330 J/s at 375°C and heat output is 800 J/s.

Each second, how much work is done in the process?

Homework Equations


QL/QH=1-e

The Attempt at a Solution


QL=(1-e)QH

QH=W/e

W=average of 1330 and 800 which is 1065J

QH=1065J/.40 (e was calculated in part A, which I don't need help on).
= 2.6625kJ

QL=(1-.40)2.6625kJ
QL=1.6kJ/s or 1.6kW

I followed an example in my textbook, the part I am confused on is how to get W, I just took the average of the two that were given.
 
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An engine converts heat to work.


So heat is input to the engine, the engine does work and rejects some heat.

If we apply conservation of energy we get.


Heat input=Work done + heat rejected
 

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