$A$ 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 ....... $J$.

$A$ refrigerator is to maintain eatables kept inside at $9^{\circ} C$. If room temperature is $36^{\circ} C$,calculate the coefficient of performance.

If the door of a refrigerator is kept open in a closed room,will the room become cooler or warmer?

If a refrigerator's door is kept open,will the room become cool or hot? Explain.

The temperatures inside and outside of a refrigerator are $260 \ K$ and $315 \ K$ respectively. Assuming that the refrigerator cycle is reversible,calculate the heat delivered to the surroundings for every joule of work done. (in $.73$)

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 $kJ/s$)