Determine the temperature at which the liquid, which is part of the humid vapor

6. Determine the temperature of water at a state of P = 400 kPa and h = 3300 kJ/kg.

2. A piston-cylinder device initially contains 0.8 kg of nitrogen gas at 160 kPa and 240 °C. The nitrogen gas is now expanded to a pressure of 100 kPa isothermally. Determine the work boundary during this process. 3. A frictionless piston-cylinder device contains 6 kg vapor at 600 kPa and 400 °C. When heat is transferred to the system, the vapor temperature is increasing up to 500 °C. Calculate the work net during this heat transfer process.

8. 1.8-m³ rigid tank contains steam at 220 °C. One-third of the volume is in the liquid phase and the rest is in the vapor form. Determine (a) the pressure of the steam, (b) the quality of the saturated mixture, and (c) the density of the mixture.

Air is contained in a vertical piston–cylinder assembly fitted with an electrical resistor. The atmosphere exerts a pressure of 101.325 kPa on the top of the piston, which has a mass of 50 kg and a face area of 0.10 m 2 . Electric current passes through the resistor, and the volume of the air slowly increases by 2 ft3 while its pressure remains constant. The mass of the air is 0.32 kg, and its specific internal energy increases by 20 Btu/lb. The air and piston are at rest initially and finally. The piston–cylinder material is a ceramic composite and thus a good insulator. Friction between the piston and cylinder wall can be ignored, and the local acceleration of gravity is g = 32.0 ft/s2 Determine the heat transfer from the resistor to the air, in Btu, for a system consisting of (a) the air alone, (b) the air and the piston. Also draw the schematic diagram. Hint: Refer to example