The figure shows the `P-V` plot of an ideal gas taken through a cycle `ABCDA`. The part `ABC` is a semi-circle and `CDA` is half of an ellipseThen

Options

A. the process during the path `A rarr B` is isothermal
B. heat flows out of the gas during the path `B rarr C rarr D`
C. work done during the path `A rarr B rarr C` is zero
D. positive work is done by the gas in the cycle `ABCDA`

Answer

B, D

Explanation

(A) process is not isothermal
(B) volume decreases and temperature decreases
`DeltaU =` negative (PV decreases)
`DeltaW = `negative
so `DeltaQ =` negative
(C ) Work done in process `A rarr B rarr C` is positive
(D) Cycle is clockwise, so work done by the gas is positive.