"Consider the dc motor whose's moment-of-inertia Jm = 0.02 kg*m^2. Its armature inductance La can be neglected for slow changes. The motor is driving a load of inertia JL = 0:04 kg*m^2. The steady state operating speed is 400 rad/s. Calculate and plot the terminal voltage va(t) that is required to bring this motor to a halt as quickly as possible, without exceeding the armature current of 12 A."

What difference(s) did you notice using a pneumatic circuit over hydraulic circuit.explain why the pneumatic piston stumbles when it hits an obstacle.

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?

The higher the astm grain size number, the finer the gran is. a)-true b)-false