If the coefficient of performance of a refrigerator is 5 and operates at the room temperature `(27^@C)`, find the temperature inside the refrigerator.

Explanation

Coefficient of performance,
`beta=5`
`T_1`=27+273=300 K
`T_2`=?
Coefficient of performance ,
`beta=T_2/(T_1-T_2)`
`therefore 5=T_2/(300-T_2)`
`therefore 1500-5T_2=T_2`
`therefore 1500=6T_2`
`therefore T_2=1500/6`=250 K
`therefore t_2`=250-273 =`-23^@`C