The coefficient of performance of a refrigerator is $5$. If the temperature inside the freezer is $-20^{\circ}C$,the temperature of the surroundings to which it rejects heat is ........ $^{\circ}C$.

$A$ refrigerator with a coefficient of performance of $1/3$ releases $200 \ J$ of heat. What is the work done on the working substance in Joules?

The temperature inside a refrigerator is $t_2 \, ^\circ C$ and the room temperature is $t_1 \, ^\circ C$. The amount of heat delivered to the room for each joule of electrical energy consumed ideally will be:

Define and write the formula for the coefficient of performance of a refrigerator.

The temperature of the freezer compartment of an ideal refrigerator is $-13 \, ^\circ C$. If the coefficient of performance of the refrigerator is $5$,then the temperature of the surroundings (to which heat is rejected) is:

The efficiency of a reversible heat engine working between two temperatures is $50 \%$. The coefficient of performance of a refrigerator working between the same two temperatures but in reverse direction is