MCQ
A Carnot engine take $5000 \,k\,cal$ of heat from a reservoir at $727\,^{\circ}C$ and gives heat to a $\operatorname{sink}$ at $127\,^{\circ}C$. The work done by the engine is $.......... \times 10^{6}\,J$
- A$3$
- B$0$
- ✓$12.6$
- D$8.4$
✓
Answer
Correct option: C.
$12.6$
c
$L=\frac{W D}{Q_{H}}$
$L=\frac{W D}{Q_{H}}$
$\Rightarrow WD = Q _{ H }\left(1-\frac{ T _{ L }}{ T _{ H }}\right)$
$=5 \times 10^{3}\left(1-\frac{400}{1000}\right)$
$=3000\, kcal$
$=12.6 \times 10^{6} J$
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