In a working refrigerator, the value of COP is always

A. 0

B. < 0

C. < 1

D. > 1

Answer: Option D

Solution(By Examveda Team)

We know COP of a refrigerator
$$\eqalign{ & = \frac{{{\text{Cooling effect}}}}{{{\text{Work taken}}}} \cr & = \frac{{{Q_L}}}{{{W_{net}}}} \cr & = \frac{{{Q_2}}}{{{Q_1} - {Q_2}}} \cr} $$
For a reversible refrigerator COP $$ = \frac{{{T_2}}}{{{T_1} - {T_2}}}$$
Since $${T_1} - {T_2} < {T_2}$$
So COP is always greater than zero.