What are the units or dimensions of the shear rate dv/dy (english units)? then, what are the dimensions of the shear stress τ= μ*dv/dy? then, by dimensional analysis, show that the shear stress has the same units as momentum divided by (area*time).what are the unit or dimensions of viscosity?

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?

Condition monitoring is a major component of. (clo4) a)- predictive maintenance. b)-preventive maintenance c)-proactive maintenance d)-reactive maintenance.

Have a greater impact on maintenance productivity than any other support group. (clo5) a)-the top management b)-inventory and purchasing c)-sub-contracting d)-cmms