Efficiency of a heat engine whose sink is at temperature of 300 K is 40% . To increase the efficiency to 60 % keeping the sink temperature same, the source temperature must be increased by

Efficiency of a heat engine whose sink is at temperature of 300 K is 4

1.	Efficiency of a heat engine whose sink is at temperature of 300 K is 40% . To increase the efficiency to 60 % keeping the sink temperature same, the source temperature must be increased by
Answer» Solution :`(T_(2))/(T_(1))=1-eta=1-(40)/(100)=(3)/(5)` `RARR T_(1)=(5)/(3)T_(2) rArr T_(1)=(5)/(3)xx300=500K` New efficiency `eta=60%` `(T_(2))/(T_(1))=1-eta=1-(60)/(100)=(2)/(5)""T_(1)=(5)/(2)xx300=750K`, `DeltaT=750-500=250K`