A heat engine operates between a hot reservoir at 500 K and a cold reservoir at 400 K
PHYSICS · Single correct · A Level · Physics · Engineering physics · Engineering physics
Problem
A heat engine operates between a hot reservoir at 500 K and a cold reservoir at 400 K. It claims an efficiency of 40 %. Which of the following statements is correct?
(a) The claim is possible because the Carnot efficiency here is 80%, which is larger than 40%.},{
(b) The claim violates the Kelvin–Planck statement because it exceeds the maximum possible efficiency.
(c) The claim violates the First Law of Thermodynamics, since the work output would exceed the heat input.
(d) The claim is possible because the efficiency is below 50%.