A vertical piston–cylinder device initially contains
0.2 m3 of air at 20°C. The mass of the piston is such that it
maintains a constant pressure of 300 kPa inside. Now a valve
connected to the cylinder is opened, and air is allowed to
escape until the volume inside the cylinder is decreased by
one-half. Heat transfer takes place during the process so that
the temperature of the air in the cylinder remains constant.
Determine (a) the amount of air that has left the cylinder and
(b) the amount of heat transfer.