A carnot engine opeates between two reservoirs of temperature 900K and 300K. The engine performs 1200J of work per cycle. The heat energy in (J) delivered by the engine to the low temperature reservoir in a cycle is

Options

A. 800J
B. 600J
C. 1800J
D. 900J

Answer

B

Explanation

Efficiency of carnot engine `eta= 1- (T_(2))/(T_(1))`
`:. eta =1- (300)/(900)`
`:. eta= 1- (1)/(3)= (2)/(3)`
and `eta= (W)/(Q)`
`:. Q_(h) = (W)/(eta)`
`Q_(h)` = Heat of source
`:. Q_(h)= (1200)/(2) xx (3)/(1)`
`:. Q_(h)= 1800J`
Now `W= Q_(h) - Q_(L)`
`:. Q_(L)= Q_(h) - W`
`=1800-1200`
`:. Q_(L)= 600J`