MCQ
If a Carnot’s engine functions at source temperature $127^o C$ and at sink temperature $87^o C$, what is its efficiency ....... $\%$
  • A
    $50$
  • B
    $25$
  • C
    $40$
  • $10$

Answer

Correct option: D.
$10$
d
(d) $\eta = \frac{{{T_1} - {T_2}}}{{{T_1}}}$$ = \frac{{(127 + 273) - (87 + 273)}}{{(127 + 273)}}$

$ = \frac{{400 - 360}}{{400}} = 0.1 \to 10\% $

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