A heat engine operating at maximum efficiency has an efficiency of 25%. The temperature of the cold reservoir is 300 K. What is the temperature of the hot reservoir?
A) 350 K
B) 375 K
C) 400 K
D) 450 K
E) 500 K

Question

Quizplus · Accepted Answer

The maximum efficiency of a heat engine is given by the equation:

Efficiency = 1 - (Tc/Th)

Where Tc is the temperature of the cold reservoir and Th is the temperature of the hot reservoir.

Plugging in the given values:

0.25 = 1 - (300/Th)

0.75 = 300/Th

Th = 400 K

Therefore, the temperature of the hot reservoir is 400 K, which corresponds to choice C).

A Heat Engine Operating at Maximum Efficiency Has an Efficiency