Carbon monoxide is carried around a closed cyclic processes `abc`, in which `bc` is an isothermal process, as shown in Fig. The gas absorbs `7000 J` of heat as its temperature is increased from `300 K` to `1000 K` in going from `a` to `b`. The quantity of heat ejected by the gas during the process `ca` is

Options

A. 4200J
B. 500J
C. 9000J
D. 9800J

Answer

D

Explanation

d. `P = 4.5 xx 10^(5) Pa, dQ = 800 J`
`V_(1) = 0.5 m^(3) , V_(2) = 2 m^(3)`
`dW = P (V_(2) - V_(1)) = 4.5 xx 10^(5) (2 xx 0.5)`
`= 6.75 xx 10^(5) J`
Change in internal energy
`dU = dQ - dW`
`= 800 xx 10^(5) - 6.75 xx 10^(5) = 1.25 xx 10^(5) J`