Question

Show that reversible expansion work of an ideal gas is greater than in an adiabatic process

Answer 1

An adiabatic process is one in which no heat enters or leaves the system, and hence, for a reversible adiabatic process the first law takes the form dU = − PdV. ... Thus for a reversible adiabatic process and an ideal gas, CVdT = −PdV. (The minus sign shows that as V increases, T decreases, as expected.)

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