The flywheel has a diameter of 500 mm and rotates with increasing speed about its z-axis shaft. When θ= 75o, point P has an acceleration given bya = -1.5 i – 4.2 j m/s2. For this instant, determine the angular velocity ω and the angular acceleration α of the flywheel.

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

Fluids at rest possess no flow energy. 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?