MULTIPLE CHOICE QUESTIONS
Q.1 The two windings of a transformer is
(A) conductively
linked.
(B) inductively
linked.
(C)
not linked at all.
Q.2 A
salient pole synchronous motor is running at no load. Its field current is switched off. The motor
will
(A) come to stop.
(B) continue to run at synchronous speed.
(C) continue to run at a speed slightly more than
the synchronous speed.
(D) continue to run at a speed slightly less than
the synchronous speed.
Q.3 The d.c. series motor should always be
started with load because
(A) at no
load, it will rotate at dangerously high speed.
(B) it will
fail to start.
(C) it will
not develop high starting torque.
(D) all are
true.
Q.4 The frequency
of the rotor
current in a
3 phase 50 Hz,
4 pole induction
motor at full load speed is about
(A) 50
Hz.
(B) 20
Hz.
(C) 2
Hz.
(D)
Zero.
Q.5 In a
stepper motor the angular displacement
(A) can be precisely controlled.
(B) it cannot be readily interfaced with micro
computer based controller.
(C) the angular displacement cannot be precisely
controlled.
(D) it cannot be used for positioning of work
tables and tools in NC machines.
Q.6 The power factor of a squirrel cage
induction motor is
(A) low at light load only.
(B) low at heavy load only.
(C) low at light and heavy load both.
(D) low at rated load only.
Q.7 Transformer core is made of:
(A) silicon sheet steel.
(B) chromel steel.
(C) low carbon steel.
(D) high content silicon steel.
Q.8 When
a synchronous motor
is running at
synchronous speed, the damper
winding produces
(A)
damping torque.
(B)
eddy current torque.
(C)
torque aiding the developed torque.
(D)
no torque.
Q.9 If
a transformer primary
is energised from
a square wave
voltage source, its
output voltage will be
(A) A
square wave.
(B) A sine wave.
(C) A
triangular wave.
(D) A pulse wave.
Q.10 In a d.c. series motor the electromagnetic
torque developed is proportional to
(A) Ia
(B) Ia2
(C)
1/Ia
