MCQ
A Carnot engine, whose efficiency is $40\%$, takes in heat from a source maintained at a temperature of $500\ K$. It is desired to have an engine of efficiency $60\%$. Then, the intake temperature for the same exhaust (sink) temperature must be ....... $K$
  • A
    $1200$
  • $750$
  • C
    $600 $
  • D
    efficiency of carnot engine cannot be made larger than $50 \%$

Answer

Correct option: B.
$750$
b
$0.4 = 1 = \frac{{{T_2}}}{{500}}\,and\,0.6 = 1 - \frac{{{T_2}}}{{{T_1}}}$

$On\,solving\,we\,get\,{T_2} = 750\,K$

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