MM0704, Lesson 3
9.
How is the torque of a shunt DC motor affected if the armature current is doubled?
a.
Halved.
b.
Reduced by one-eighth.
c.
Increased by one-fourth.
d.
Doubled.
10.
What characterizes a DC shunt motor?
a.
Constant speed.
b.
Varying speed and constant torque.
c.
d.
Varying torque and varying speed.
11.
a.
b.
f = PN x 120.
c.
d.
f = PN x 60.
12.
What is the difference, in degrees, between windings of a three-phase generator?
a.
45.
b.
60.
c.
90.
d.
120.
13.
How many rpm must a four-pole AC generator make in order to generate an output frequency of 60 Hz?
a.
1,100.
b.
1,600.
c.
1,800.
d.
2,200.
14.
Which motor is normally used for timing devices?
a.
DC series.
b.
AC series.
c.
Compound.
d.
Synchronous.
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