MCQ
For which combination of working temperatures the efficiency of Carnot's engine is highest
- A$80 K, 60 K$
- B$100 K, 80 K$
- C$60 \mathrm{~K}, 40 \mathrm{~K}$
- ✓$40 K, 20 K$
✓
Answer
Correct option: D.
$40 K, 20 K$
$\eta=1-\frac{T_2}{T_1}$.
for $\eta$ to be max. ratio $\frac{T_2}{T_1}$ should be min.
for $\eta$ to be max. ratio $\frac{T_2}{T_1}$ should be min.
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