Question

An ideal gas is expanded isothermally from volume V₁ to volume V₂ and then compressed adiabatically to original volume V₁. If the initial pressure is P₁, the final pressure is P₃ and net work done is W, then ____________.

Options

• P₃ >P₁, W > 0

• P₃ < P₁, W < 0

• P₃ > P₁, W < 0

• P₃ = P₁, W = 0

Answer 1

An ideal gas is expanded isothermally from volume V₁ to volume V₂ and then compressed adiabatically to original volume V₁. If the initial pressure is P₁, the final pressure is P₃ and net work done is W, then P₃ > P₁, W < 0.

Explanation:

Figure shows the PV diagram of the given process.

From figure it can be said that, area under the curve for isothermal expansion is lesser than area under the curve for adiabatic compression.

∴ The work done is negative. Also, pressure P₃ > P₁