A heat engine with an output of 300 W has an efficiency of 25% and works at 10 cycles/s.How much heat is absorbed (Q_h)and how much rejected (Q_c)in each cycle?

Question

Quizplus · Accepted Answer

The efficiency of the heat engine is given as 25%, which can be written as:
efficiency = work output / heat input
0.25 = 300 / heat input
heat input = 300 / 0.25 = 1200 J

In each cycle, the work output is:

work output = efficiency * heat input
work output = 0.25 * 1200 J = 300 J

Since the heat engine works at 10 cycles/s, the heat absorbed and rejected in each cycle can be calculated as:

heat absorbed per cycle = heat input / 10
heat absorbed per cycle = 1200 J / 10 = 120 J

heat rejected per cycle = heat input - work output
heat rejected per cycle = 1200 J - 300 J = 900 J

Therefore, the correct answer is D.

A Heat Engine with an Output of 300 W Has