MCQ
If a Carnot engine works between $127^{\circ} C$ and $527^{\circ} C$, then its efficiency is ...... $\%$
- A$25$
- B$37.5$
- ✓$50$
- D$75$
✓
Answer
Correct option: C.
$50$
c
(c)
(c)
$T _1=127^{\circ}\,C =400\,K$
$T _2=527^{\circ}\,C =800\,K$
Efficiency $=\eta=1-\frac{T_1}{T_2}$
$=1-\frac{400}{800}=\frac{1}{2}$
Percentage efficiency $=\frac{1}{2} \times 100=50 \%$
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