A three-phase generator is Y-connected. It has phase voltages of 277 V. A delta-connected load is attached to the lines coming from the generator. Each phase of the load has an impedance of 9|41°ohm. (a) Sketch and label the circuit. Find (b) the magnitude of the phase current in the load, (c) the line current, and (d) the total power consumed by the load

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?