Army Group X Practice Set 2

Coefficient of performance (α) of refrigerator is defined as heat extracted per unit work done. It may be more than one, it cannot be infinite.
α=‌

Q2

Q1W

=‌

‌ Heat extracted ‌

‌ Work done ‌

=‌

Q1

W

(for refrigerator)
Here, Q1=W+Q2= Heat released to net reservoir
Q2=Q1−W⇒α=‌

Q2

Q1−Q2