Figure shows the variations of the internal energy `U` With density `rho` one mole an ideal monatomic gas for thermodynamic cycle `ABCA` . Here process `AB` is a part of rectangular hyperbola,-

Options

A. process `AB` is isothermal & net work in cycle is done by gas.
B. process `AB` is isobaric & net work in cycle is done by gas.
C. process `AB` is isobaric & net work in cycle is done on the gas.
D. process `AB` is adiabatic & net work in cycle is done by gas.

Answer

B

Explanation

For the process `AB` : `Urho` = constant (hyperbola )
`U=(3)/(2)RT` (monoatomic iddeal gas), `(3)/(2)rhoRT` = constant
Comparing it with ideal gas equation ` P = ((1)/(M))rhoRT implies P` is constant.
`P-V` graph for the cycle is . Thus work done in cycle positive