The coefficient of performance of a Carnot refrigerator working between temperatures $30 \, ^\circ\text{C}$ and $0 \, ^\circ\text{C}$ is:

$A$ Carnot's engine works as a refrigerator between $250\, K$ and $300\, K$. It receives $500\, cal$ heat from the reservoir at the lower temperature. The amount of work done in each cycle to operate the refrigerator is ..... $J$

$A$ refrigerator consumes an average $35 \ W$ power to operate between temperatures $-10^{\circ}C$ and $25^{\circ}C$. If there is no loss of energy,how much average heat per second does it transfer? (in $J/s$)

The coefficient of performance of a refrigerator working at a temperature of $27^{\circ} C$ is $5$. Find the temperature inside the refrigerator. (in $K$)

The equation $\beta = \frac{Q_2}{Q_1 - Q_2}$ is true or false?

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