Question

If the energy removed from an engine as heat
during one cycle is 7.0 × 102
J, how much
energy must be added to the engine during
one cycle in order for it to operate at 36
percent efficiency?
Answer in units of J.

Answer 1

Let Q be the energy added to the engine. We have

0.36 = [1 - (700/Q)]

[1- (36/100)] = (700/Q)

Q = 1100 J