Heat extract from refrigerator, Qc
Heat deliver to surrounding, Qh
Temperature of refrigerator, T2
Temperature of surrounding, T1
For refrigerator,
C.O.P=T2T1−T2=QcW
⇒QcW=260315−260=4.64
⇒Qc=W×4.64
Heat deliver to surrounding
Qh=Qc+W=W(4.64+1)
⇒QhW=5.64
5.64J heat deliver to surrounding per unit joule work done.