Refrigerator A works between- `10^(@)C and 27^(@)C` while refrigerator B works between `-20^(@)C and 17^(@)C`, both removing `2000J` from the freezer. Which of the two is better refrigerator?

Answer

A is better

Explanation

For refrigerator A,
`T_(2)=10^(@)C= (-10+273)K=263K`
`T_(2)= 27^(@)C=27+273= 300K`
`COP=(T_(2))/(T_(1)-T_(2))= (263)/(300-263)= (263)/(37)`
For refrigerator B
`T_(2)= -20^(@)C=(-20+273)K=253K`
`T_(1)= 17^(@)C= (17+273)K=290K`
`COP=(T_(2))/(T_(1)-T_(2))= (253)/(290-253)= (253)/(37)`
As `(COP)_(A)gt(COP)_(B)`
`:.` Refrigeraotr A is better than B.