The temperatures inside and outside a refrigerator are $273 \, K$ and $300 \, K$ respectively. Assuming that the refrigerator cycle is reversible,for every joule of work done,the heat delivered to the surrounding will be nearly ........ $J$.

The coefficient of performance of a Carnot refrigerator working between $30^oC$ and $0^oC$ is

In a cold storage,ice melts at the rate of $2 \ kg$ per hour when the external temperature is $20^{\circ} C$. The minimum power output of the motor used to drive the refrigerator which just prevents the ice from melting is (latent heat of fusion of ice $= 80 \ cal \ g^{-1}$) (in $W$)

The efficiency of a Carnot engine acting as a heat engine is $\eta = 1/10$. If it is used as a refrigerator and the work done on the system is $10 \ J$,then the heat absorbed from the low-temperature reservoir is ...... $J$.

$A$ Carnot engine,having an efficiency of $\eta = 1/10$ as a heat engine,is used as a refrigerator. If the work done on the system is $10 \ J$,the amount of energy absorbed from the reservoir at a lower temperature is ....... $J$.

Is the coefficient of performance of a refrigerator constant?