1 kg of steam at 100 bar and 375°C expands reversibly in a perfectly thermally insulated cylinder behind a piston until pressure is 38 bar and the steam is then saturated.
Calculate the work done by the steam.
1 kg of steam at 20 bar, dryness fraction 0.9, is heated reversibly at constant pressure to a temperature of 300°C.
Calculate the heat supplied and change of entropy and show the process on a T-s diagram, indicating the area which represents the heat flow.