Question

A heat engine operating between energy reservoirs at 20 C and 600 C has 30% of the maximum possible efficiency.

a) True
b) False

Answer 1

The statement is (a) True.

Step-by-step explanation:

The maximum efficiency of a heat engine operating between hot and cold reservoir temperatures can be determined using the formula for Carnot efficiency, which is given by:

Efficiency = 1 - (Tc/Th)

Where Tc is the temperature of the cold reservoir and Th is the temperature of the hot reservoir. In this case, the efficiency is 30% of the maximum possible efficiency. Therefore, we can set up the following equation:

0.30 = 1 - (Tc/Th)

Solving for Tc/Th, we get:

Tc/Th = 0.70

Since Tc/Th is less than 1, we can conclude that the cold reservoir temperature is less than the hot reservoir temperature. Therefore, the statement is True.