The cofficient of performance of a refrigerator is 5. If the temperature inside freezer is `-20^(@)C`, the temperature of the surroundings to which it rejects heat is :

Options

A. `21^(@)C`
B. `31^(@)C`
C. `41^(@)C`
D. `11^(@)C`

Answer

B

Explanation

Coefficient of performance of refrigerator
COP`=(T_(L))/(T_(H)--T_(L))`
Where `T_(L)to` lower temperature
& `T_(H)to`Higher temperature
So, `5=(T_(L))/(T_(H)--T_(L))`
`implies T_(H)=(6)/(5)T_(L)=(6)/(5)(253)=303.6K`.