Heat is allowed to flow from the heat source of a heat engine at 425 K to a cold sink at 313 K. What is the efficiency of the heat engine? The answer should have three significant figures.
The efficiency of a heat engine is given by the formula:
Efficiency = (1 - Tcold/Thot) * 100%
where Tcold is the temperature of the cold sink and Thot is the temperature of the heat source.
Plugging in the values:
Efficiency = (1 - 313 K / 425 K) * 100%
= (1 - 0.736) * 100%
= 26.4%
Therefore, the efficiency of the heat engine is 26.4%.