Question

A refrigerator removes 1.5 kJ from the cold space using 1 kJ work input. How much energy goes into the kitchen and what is its coefficient of performance?

Answer 1

C.V. Refrigerator. The energy QH goes into the kitchen air.  

Energy Eq.: QH = W + QL

 = 1 + 1.5 = 2.5 kJ

COP: β = QL/W = 1.5 / 1 = 1.5

The back side of the refrigerator has a black grille that heats the kitchen air. Other models have that at the bottom with a fan to drive the air over it.