Question

a carnot refrigerator has a cop of 6. what is the ratio of the lower to the higher absolute temperature

Answer 1

a Carnot refrigerator has a cop of 6 .
cop means coefficient of performance of refrigerator.
formula of cop is given by $cop=\frac{T_1}{T_2-T_1}$
where $T_1$ is lower temperature
$T_2$ is higher temperature.

now, $cop=\frac{T_1}{T_2-T_1}$

$6=\frac{T_1}{T_2-T_1}$

$6(T_2-T_1)=T_1$

$6T_2=7T_1$

$\frac{T_1}{T_2}=\frac{6}{7}$

hence, 6/7 is the ratio of the lower temperature to higher temperature.