MCQ
A reversible heat engine converts one-fourth of the heat input into work. When the temperature of the sink is reduced by $52\, K$, its efficiency is doubled. The temperature in Kelvin of the source will be ...... .
- A$256$
- ✓$208$
- C$104$
- D$52$
✓
Answer
Correct option: B.
$208$
b
$\eta=\frac{1}{4}=1-\frac{ T _{2}}{ T _{1}}$
$\eta=\frac{1}{4}=1-\frac{ T _{2}}{ T _{1}}$
$\frac{ T _{2}}{ T _{1}}=\frac{3}{4}$
$\frac{ T _{2}-52}{ T _{1}}=\frac{1}{2}$
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