Question

A completely reversible heat engine operates with a source at 1500 K and a sink at 300 K. What is the maximum efficiency of this engine?

a) 20%
b) 50%
c) 80%
d) 100%

Answer 1

The maximum efficiency of a completely reversible heat engine operating between temperatures of 1500 K and 300 K is 80%.

Step-by-step explanation:

The maximum efficiency of a completely reversible heat engine can be determined using the Carnot efficiency formula:

Efficiency = 1 - (Tcold/T)

where Tcold is the temperature of the sink and T is the temperature of the source. In this case, the sink temperature is 300 K and the source temperature is 1500 K, so the efficiency is:

Efficiency = 1 - (300/1500) = 1 - 0.2 = 0.8 = 80%

Therefore, the maximum efficiency of this engine is 80%.