MCQ
The efficiency of Carnot's engine operating between reservoirs, maintained at temperatures $27^{\circ} \mathrm{C}$ and $-123^{\circ} \mathrm{C}$, is
- ✓$50 \%$
- B$24 \%$
- C$0.75 \%$
- D$0.4 \%$
✓
Answer
Correct option: A.
$50 \%$
(a) $\quad \eta=1-\frac{T_2}{T_1}=1-\frac{(273+123)}{(273+27)}=1-\frac{150}{300}=\frac{1}{2}=50 \%$
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