Water initially at 200 kpa and 300degrees c is contained in a piston-cylinder device fitted with stops. the water is allowed to cool at constant pressure until it exists as a saturated vapor and the piston rests on the stops. then the water continues to cool until the pressure is 100 kpa. a) on the t-v diagrams sketch with respect to the saturation lines, the process curves passing through both the initial, intermediate, and final states of the water. b) label the t, p and v values for end states on the process curves. c) find the overall change in internal energy between the initial and final states per unit mass of water.

Ahouse has the following electrical appliance usage (1) single 40w lamp used for 4 hours per day (2) single 60w fan used for 12 hours per day (3) single 200w refrigerator that runs 24 hours per day with compressor run 12 hours and off 12 hours find the solar power inverter size in watt with correction factor of 1.25.

Acompressor receives the shaft work to decrease the pressure of the fluid. a)- true b)- false

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?