A) 80°C, 37°C
B) 95°C, 28°C
C) 90°C, 37°C
D) 99°C, 37°C
Correct Answer: D
Solution :
Initially \[\eta =\left( 1-\frac{{{T}_{2}}}{{{T}_{1}}} \right)=\frac{W}{Q}=\frac{1}{6}\] ...(i) Finally \[\eta '=\left( 1-\frac{{{T}_{2}}'}{{{T}_{1}}} \right)=\left( 1-\frac{({{T}_{2}}-62)}{{{T}_{1}}} \right)=1-\frac{{{T}_{2}}}{{{T}_{1}}}+\frac{62}{{{T}_{1}}}\] \[=\eta +\frac{62}{{{T}_{1}}}\] ....(ii) It is given that \[\eta '=2\eta .\] Hence solving equation (i) and (ii) Þ \[{{T}_{1}}=372\,K=99{}^\circ C\] and \[{{T}_{2}}=310K=37{}^\circ C\]You need to login to perform this action.
You will be redirected in
3 sec