Q. A scientist says that the efficiency of his heat engine which operates at source temperature $127℃$ and sink temperature $27℃$ is 26%, then
A) It is impossible
B) It is possible but less probable
C) It is quite probable
D) Data is incomplete
Explanation
(a) $\eta_{\max} = 1 - \frac{T_{2}}{T_{1}} = 1 - \frac{300}{400} = \frac{1}{4} = 25\%$
So 26% efficiency is impossible
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.