A Carnot engine used first ideal monoatomic gas and then an ideal diatomic gas , if the source and sink temperatures are `411^(@)C` and `69^(@)C` ,respectively and the engine extracts 1000 J of heat from the source in each cycle , then

Options

A. area enclosed by the p-V diagram is 10 J
B. heat energy rejected by engine is 1 st case is 600 J while that in 2 nd case in 113 J
C. area enclosed by the p-V diagram is 500 J
D. efficiencies of the engine in both the cases are in the ratio 21 : 25

Answer

C

Explanation

Here , `T_(1)=411^(@)C=(411+273)K=684K`
`T_(2)=69^(@)C=(69+273)K=342Kand Q_(1)=1000J`
`because"Efficiency "eta=(W)/(Q_(1))=1-(T_(2))/(T_(1))=1-(342)/(684)=(1)/(2)`
`rArr" " W=etaQ_(1)=(1000)/(2)=500J`