Q. An engine operating between $150℃$ and $25℃$ takes 500 J heat from a higher temperature reservoir if there are no frictional losses, then work done by engine is

A) 165.85 J
B) 169.95 J
C) 157.75 J
D) 147.7 J
Explanation

(d)
$T_{2} = 150 + 273 = 423$ K,
$T_{1} = 25 + 273 = 298$ K
$Q = 500$ K
$\frac{W}{Q} = \frac{T_{2} - T_{1}}{T_{2}}$
$\therefore W = 500\ \left( \frac{423 - 298}{423} \right) = 147.7\ J$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.