What is the maximum theoretical efficiency for an engine operating between 100°C and 400°C?
A) 25%.
B) 45%.
C) 55%.
D) 75%.

Question

Quizplus · Accepted Answer

The maximum theoretical efficiency of an engine is given by the Carnot efficiency, which is 1 - (T_cold/T_hot), where temperatures are in Kelvin. Converting the given temperatures to Kelvin gives 373K (100°C) and 673K (400°C). Thus, the efficiency = 1 - (373/673) = 0.446, or 44.6%, which rounds to 45%.

What Is the Maximum Theoretical Efficiency for an Engine Operating