A cylinder of free volume 10ft3 is divided into two compartments by a piston. Originally the piston is at one end and the cylinder contains 2lb of steam at 150C. Air from a supply main at 200lb/in2 and 15C is then admitted slowly via a throttle valve to the other side of the piston. Estimate the temperature of the air when pressure equilibrium is reached.
Neglect any heat loss from the cylinder as well as assume no heat transfer across the piston. Define clearly any assumption made. [Note. Use Steam Tables]