N moles of gas an ideal mono atomic gas is confined in a cylinder A of volume
V0, pressure
P0 and temperature
T0, this cylinder is connected to another cylinder B with the help of tube of a negligible volume. The cylinder B is fitted with a movable piston which can be adjusted from outside. Initially, the piston is adjusted so that volume of B is 7
V0 and B is evacuated and then stop-cork is opened so that gas expands and occupies the volume
8V0.
[System is thermally isolated from the surroundings].
Now with the stop-cork open. The piston is slowly moved to compress the gas back to cylinder A. For this work done on the gas :