The efficiency of a Carnot engine operating between reservoirs maintained at temperatures $27^{\circ}C$ and $-123^{\circ}C$ is ...... $\%$

The efficiency of a Carnot cycle is $\frac{1}{6}$. By lowering the temperature of the sink by $65 \ K$,it increases to $\frac{1}{3}$. The initial and final temperatures of the sink are:

The efficiency of a Carnot engine is $0.6$. It rejects a total of $20 \ J$ of heat. The work done by the engine is .... $J$.

The efficiency of a reversible engine is . . . . . . the efficiency of an irreversible engine.

In a Carnot engine,when ${T_2} = {0^o}C$ and ${T_1} = {200^o}C$,its efficiency is ${\eta _1}$. When ${T_1} = {0^o}C$ and ${T_2} = -{200^o}C$,its efficiency is ${\eta _2}$. What is the ratio ${\eta _1}/{\eta _2}$?

In a Carnot engine,if the work done during isothermal expansion is $25 \%$ more than the work done during isothermal compression,then the efficiency of the engine is: (in $\%$)