Practice problems
refer to the circuit shown in figure 17-2 and the resistive-inductive series circuits section of the ac
formulas listed in appendix b.
1. assume that the circuit shown in figure 17-2 is connected to a 40
snown in figure 17-2 is connected to a 480-v, 60-hz line. the inductor
has an inductance of 0.053 h, and the resistor has a resistance of 1
et 480v
er
el
i
n
r 12 12
x
od
va
varsl
pf
ce
l 0.053 h
a
+
+
+
answers

Line joining liquid phase with liquid and solid phase mixture is known as: a) liquidus b) solidus c) tie line d) none of the mentioned

Aflywheel accelerates for 5 seconds at 2 rad/s2 from a speed of 20 rpm. determine the total number of revolutions of the flywheel during the period of its acceleration. a.5.65 b.8.43 c. 723 d.6.86

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?