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goblinko [34]
3 years ago
13

In a heat engine, Qh and Qc represents high temperature substance and low temperature substance respectively. Which of the follo

wing expressions is correct for the efficiency of the heat engine?

Physics
1 answer:
ElenaW [278]3 years ago
6 0

The efficiency of a heat engine is given by the expression eff =\frac{Q_h-Q_c}{Q_h}

The efficiency of a heat engine is the ratio of the work done by the engine to the heat given as the input to the engine.

eff =\frac{W}{Q_h}

The heat engine absorbs Q h from the hot reservoir , performs a work <em>W</em> on the absorbed heat and rejects Qc to the cold reservoir.

Therefore, the work done  is given by,

W=Q_h - Q_c

Thus the efficiency is given by, eff =\frac{Q_h-Q_c}{Q_h}

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