Define about the Modified Joule-Thomson?

Container A of variable volume V controlled by a frictionless piston immersed in a bath at temperature T.  This container is connected by a pipe with a porous plug to another container, B, of fixed volumeV¹. Container A is primarily occupied by an ideal gas at pressure P while container B is primarily evacuated.

The gas is authorized to flow through the plug and the pressure on the piston is maintained at the constant value P. While the pressure of the gas in B reaches P the experiment is terminated.  Abandon any heat conduction through the plug show that the final temperature of the gas in B is T1= (C_p/C_v) where C_p and C_v are the molar heats at constant pressure and volume of the gas.