Refrigerant 134a is the working fluid in a vapor compression heat pump that provides 30 kw to heat a dwelling on a day when the outside temperature is below freezing. saturated vapor enters the compressor at 1.8 bar, and saturated liquid exits the condenser, which operates at 9 bar. the compressor efficiency is 78%. determine for isentropic compression a) sketch the t-s diagram of the cycle b) the refrigerant mass flow rate, in kg/s. c) the compressor power, in kw. d) the coefficient of performance.

Amass of 3 kg of saturated liquid-vapor mixture of water is contained in a piston-cylinder device at 150 kpa. initially, 1 kg of the water is in the liquid phase and the rest is in the vapor phase. heat is now transferred to the water, and the piston, which is resting on a set of stops, starts moving when the pressure inside reaches 500 kpa. heat transfer continues until the total volume increases by 20 percent. determine (a)-the initial and final temperatures, (b)-the mass of liquid water when the piston first starts moving, and (c)-the work done during this process. d)-show the process on a p-v diagram. you don't need to indicate p& v values, but clearly indicate where all states are located in the phase diagram.