In a Carnot engine,if the absolute temperature of the source is $25 \%$ more than the absolute temperature of the sink,then the efficiency of the engine is (in $\%$)

If the ratio of the absolute temperature of the sink and source of a Carnot engine is changed from $2:3$ to $3:4$,the efficiency of the engine changes by (in $\%$)

One mole of an ideal monoatomic gas undergoes the following four reversible processes:
Step $1$: It is first compressed adiabatically from volume $V_{1}$ to $1 \; m^{3}$.
Step $2$: Then expanded isothermally to volume $10 \; m^{3}$.
Step $3$: Then expanded adiabatically to volume $V_{3}$.
Step $4$: Then compressed isothermally to volume $V_{1}$.
If the efficiency of the above cycle is $3/4$, then $V_{1}$ is ............ $m^{3}$.

In a Carnot engine,if the temperatures of the source and the sink are decreased by $100 \ K$ each,then the efficiency of the engine:

Determine the efficiency of a Carnot cycle if,in the adiabatic expansion,the volume becomes $3$ times its initial value and $\gamma = 1.5$.

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