If $\alpha$ is the coefficient of performance of a refrigerator and $Q_1$ is the heat released to the hot reservoir,then the heat extracted from the cold reservoir $Q_2$ is

$A$ Carnot freezer takes heat from water at $0\,^{\circ}C$ inside it and rejects it to the room at a temperature of $27\,^{\circ}C$. The latent heat of ice is $336 \times 10^3\, J\,kg^{-1}$. If $5\, kg$ of water at $0\,^{\circ}C$ is converted into ice at $0\,^{\circ}C$ by the freezer,then the energy consumed by the freezer is close to

In a refrigerator,heat is removed from a low-temperature reservoir and deposited at a high-temperature reservoir. This requires mechanical work,which is provided by an electric motor. If the motor power is $1 \ kW$ and heat is transferred from $-3^{\circ} C$ to $27^{\circ} C$,calculate the heat removed from the refrigerator per second,assuming the efficiency is $50\%$ of the ideal Carnot refrigerator. (in $kJ/s$)

An ideal heat engine has an efficiency $\eta$. The coefficient of performance of the engine when driven backward will be

Freezing compartment of a refrigerator is at $0^{\circ} C$ and room temperature is $27.3^{\circ} C$. Work done by the refrigerator to freeze $1 \ g$ of water at $0^{\circ} C$ is $(L_{\text{ice}} = 80 \ cal \ g^{-1})$. (in $J$)

The power of a refrigerator that can make $15 \ kg$ of ice at $0^{\circ}C$ from water at $30^{\circ}C$ in one hour is: (in $W$)