Derive the equation for `'W_("rev")'` in isothermal reversible process.

Explanation

Derivation of equation for Wein isothermal reversible process:
Let the work done against the pressure `Sw =-P.dv`
Assume that expansion isothermally from volume `V_1` to volume `V_2`
`W=-underset(v_(1))overset(v_(2))int pdv " [P=pressure (External), dv=change in volume"]`
`=underset(v_(1))overset(v_(2))int (nRT)/V dv [-pv=nRT rArr (nRT)/(v)]`
`=nrT underset(v_(1))overset(v)int (dv)/v=-nRT ln V_2/V_1`
`W=-2.303nRT log""P_1/P_2`