Ahelical compression spring is wound using 2.5 mm diameter music wire. the spring has an outside diameter of 31 mm with squared ground ends, and 14 total coils. a) estimate the spring rate b) estimate the static load corresponding to the yield strength c) what should the free length be to ensure that when the spring is compressed solid the torsional stress does not exceed the yield strength? d) determine if the spring might buckle in service.

What precautions should you take to prevent injuries when dealing with heavy loads?

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?