Question

A certain heat engine draws 500cal/s from a water bath at 27°c and rejects 400cal/s to a reservoir at lower temperature .What is the efficiency of this engine? ​

Answer 1

Answer::

Q(input) = 500 cal/s

Q(heat loss) = 400 cal/s

Q(useful work) = (500 - 400) cal/sec = 100 cal/sec

E(efficiency) = 100 / 500 = 20%