The volume `(V)` of a manatomic gas varies with its temperature `(T)` , as shown in the graph. The ratio of work done by the gas, to the heat absorbed by it, when it undergoes a change from state `A` to `B` , is

Options

A. `2/7`
B. `2/5`
C. `1/3`
D. `2/3`

Answer

B

Explanation

`V prop T`
Isobaric process
`W = PDeltaV = muR DeltaT`
`Delta Q = mu C_(P)Delta T`
For monoatomic gas `f = 3`
`C_(P)=(f/2 R+R) = 5/3R`
So, `(W)/(Delta Q) = (muRDeltaT)/(mu C_(P)Delta T) = 2/5`.