Explore topic-wise MCQs in Electrical Engineering.

This section includes 240 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering knowledge and support exam preparation. Choose a topic below to get started.

101.

If a single phase induction motor runs slower than normal, the most likely defect is

A. worn bearings
B. short-circuit in the winding
C. open-circuit in the winding
D. none of the above
Answer» B. short-circuit in the winding
Discussion
102.

Which of the following single-phase motors has relatively poor starting torque ?

A. Universal motor
B. Repulsion motor
C. Capacitor motor
D. All single phase motors have zero starting torque
Answer» D. All single phase motors have zero starting torque
Discussion
103.

Which of the following statements regarding hysteresis motor is in incorrect ?

A. It is extremely sensitive to fluctuations in supply voltage
B. Its high starting torque is due to its high rotor hysteresis loss
C. It is extremely quiet in operation
D. It accelerates from rest to full-speed almost instantaneously
Answer» B. Its high starting torque is due to its high rotor hysteresis loss
Discussion
104.

Centrifugal switch disconnects the auxiliary winding of the motor at about ____ percent of synchronous speed

A. 30 to 40
B. 70 to 80
C. 80 to 90
D. 100
Answer» C. 80 to 90
Discussion
105.

In repulsion motor direction of rotation of motor

A. is opposite to that of brush shift
B. is the same as that of brush shift
C. is independent of brush shift
D.
Answer» C. is independent of brush shift
Discussion
106.

In a universal motor, the most common cause of brush sparking is

A. open armature winding
B. shorted armature winding
C. shorted field winding?
D. high commutator mica
E. all of the above
Answer» F.
Discussion
107.

In a shaded pole single-phase motor, the revolving field is produced by the use of

A. inductor
B. capacitor
C. resistor
D. shading coils
Answer» E.
Discussion
108.

In which single-phase motor, the rotor has no teeth or winding ?

A. Split phase motor
B. Reluctance motor
C. Hysteresis motor
D. Universal motor
Answer» D. Universal motor
Discussion
109.

Which of the following motors is inherently self starting ?

A. Split motor
B. Shaded-pole motor
C. Reluctance motor
D. None of these
Answer» C. Reluctance motor
Discussion
110.

A centrifugal switch is used to disconnect starting winding when motor has

A. run for about 1 minute
B. run for about 5 minutes
C. picked up about 50 to 70 per cent of rated speed
D. picked up about 10 to 25 per cent of rated speed
Answer» D. picked up about 10 to 25 per cent of rated speed
Discussion
111.

In A.C. series motor compensating winding is employed to

A. reduce the effects of armature reaction
B. increase the torque
C. reduce sparking at the brushes
D. none of the above
Answer» D. none of the above
Discussion
112.

The electric motor used in portable drills is

A. capacitor run motor
B. hysteresis motor
C. universal motor
D. repulsion motor
Answer» D. repulsion motor
Discussion
113.

Which of the following statements regarding two value capacitor motor is incorrect ?

A. It is a reversing motor
B. It is preferred to permanent-split single-value capacitor motor where frequent reversals are required
C. It has low starting as well as rushing currents
D. It has high starting torque
Answer» C. It has low starting as well as rushing currents
Discussion
114.

Speed control of a universal motor is achieved by

A. Varying field flux with tapped field windings
B. Connecting rheostat in series
C. Applying variable voltage by means of silicon controlled rectifier
D. All of the above methods
Answer» E.
Discussion
115.

Torque developed by a single phase induction motor at starting is

A. pulsating
B. uniform
C. none of the above
D. nil
Answer» E.
Discussion
116.

The speed of a universal motor is generally reduced by using

A. gear trains
B. V-belts
C. brakes
D. chains
Answer» B. V-belts
Discussion
117.

The motor used on small lathes is usually

A. universal motor
B. D.C. shunt motor
C. single-phase capacitor run motor
D. 3-phase synchronous motor
Answer» D. 3-phase synchronous motor
Discussion
118.

When a D.C. series motor is connected to A.C. supply, the power factor will be low because of

A. high inductance of field and armature circuits
B. induced current in rotor due to variations of flux
C. fine copper wire winding
D. none of the above
Answer» B. induced current in rotor due to variations of flux
Discussion
119.

A universal motor is one which

A. can be operated either on D.C. or A.C. supply at approximately the same speed and output
B. can be marketed internationally
C. runs at dangerously high speed on no-load
D. none of the above
Answer» B. can be marketed internationally
Discussion
120.

To reverse the direction of rotation of acapacitor start motor while it is running we should

A. disconnect motor from the supply till it stops then reconnect it to supply with reversed connection of main or auxiliary winding
B. disconnect motor from supply and immediately reconnect it to supply with reversed con-nections of the main winding
C. reverse the direction of connection of the auxiliary winding and after motor comes to rest then connect auxiliary winding to the supply
D. reverse the direction of connections of the auxiliary winding and immediately connect it to supply
Answer» B. disconnect motor from supply and immediately reconnect it to supply with reversed con-nections of the main winding
Discussion
121.

Starting winding of a single phase motor of a refrigerator is disconnected from the circuit by means of a

A. Magnetic relay
B. Thermal relay
C. Centrifugal switch
D. None of the above
Answer» B. Thermal relay
Discussion
122.

Which of the following motors is used in mixies ?

A. Repulsion motor
B. Reluctance motor
C. Hysteresis motor
D. Universal motor
Answer» E.
Discussion
123.

Which of the following motors is preferred for tape-recorders?

A. Shaded pole motor
B. Hysteresis motor
C. Two value capacitor motor
D. Universal motor
Answer» C. Two value capacitor motor
Discussion
124.

Which type of load is offered by cranes and hoists ?

A. Gradually varying load
B. Non-reversing, no-load start
C. Reversing, light start
D. Reversing, heavy start
Answer» E.
Discussion
125.

The wattage rating for a ceiling fan motor will be in the range%!

A. 200 to 250 W
B. 250 to 500 W
C. 50 to 150 W
D. 10 to 20 W
Answer» D. 10 to 20 W
Discussion
126.

The direction of rotation of universal motor can be reversed the by reversing the flow of current through%!

A. Armature winding
B. Field winding
C. Either armature winding or field winding
D. None of the above
Answer» D. None of the above
Discussion
127.

Which of the following motors is used for unity power factor ?%!

A. Hysteresis motor
B. Schrage motor
C. Universal motor
D. Reluctance motor
Answer» C. Universal motor
Discussion
128.

Which of the following motors can be used for unity power factor ?%!

A. Capacitor run motor
B. Shaded pole motor
C. Hysteresis motor
D. Schrage motor
Answer» E.
Discussion
129.

A centrifugal switch is used to disconnect starting winding when motor has%!

A. run for about 1 minute
B. run for about 5 minutes
C. picked up about 50 to 70 per cent of rated speed
D. picked up about 10 to 25 per cent of rated speed
Answer» D. picked up about 10 to 25 per cent of rated speed
Discussion
130.

In a shaded pole single-phase motor, the revolving field is produced by the use of%!

A. inductor
B. capacitor
C. resistor
D. shading coils
Answer» E.
Discussion
131.

The speed of a universal motor is generally reduced by using%!

A. gear trains
B. V-belts
C. brakes
D. chains
Answer» B. V-belts
Discussion
132.

Which of the following statements regarding two value capacitor motor is incorrect ?%!

A. It is a reversing motor
B. It is preferred to permanent-split single-value capacitor motor where frequent reversals are required
C. It has low starting as well as rushing currents
D. It has high starting torque
Answer» C. It has low starting as well as rushing currents
Discussion
133.

A universal motor is one which%!

A. can be operated either on D.C. or A.C. supply at approximately the same speed and output
B. can be marketed internationally
C. runs at dangerously high speed on no-load
D. none of the above
Answer» B. can be marketed internationally
Discussion
134.

*/*_If a single phase induction motor runs slower than normal, the most likely defect is?

A. worn bearings
B. short-circuit in the winding
C. open-circuit in the winding
D. none of the above
Answer» B. short-circuit in the winding
Discussion
135.

*/*_If the centrifugal switch of a two-value capacitor motor using two capacitors fails to open then?

A. motor will not come up to speed
B. motor will not carry the load
C. current drawn by the motor will be excessively high
D. electrolytic capacitor will, in all probability, suffer break down
Answer» E.
Discussion
136.

*/*_The repulsion start induction run motor is used because of?

A. good power factor
B. high efficiency
C. minimum cost
D. high starting torque
Answer» E.
Discussion
137.

*/*_In case of a shaded pole motor the direction of rotation of the motor is?

A. from main pole to shaded pole
B. from shaded pole to main pole
C. either of the above depending on voltage
D. either of the above depending on power factor
Answer» B. from shaded pole to main pole
Discussion
138.

*/*_Which of the following motor will give the highest starting torque ??

A. D.C. shunt motor
B. Schrage motor
C. Repulsion start and induction run motor
D. Universal motor
Answer» C. Repulsion start and induction run motor
Discussion
139.

*/*_In repulsion motor, zero torque is developed when?

A. brush axis is 45° electrical to field axis
B. brush axis coincides with the field axis
C. brush axis is 90° electrical to field axis
D. both (B) and (C)
Answer» E.
Discussion
140.

*/*_In a shaded pole single-phase motor, the revolving field is produced by the use of?

A. inductor
B. capacitor
C. resistor
D. shading coils
Answer» E.
Discussion
141.

*/*_A centrifugal switch is used to disconnect starting winding when motor has?

A. run for about 1 minute
B. run for about 5 minutes
C. picked up about 50 to 70 per cent of rated speed
D. picked up about 10 to 25 per cent of rated speed
Answer» D. picked up about 10 to 25 per cent of rated speed
Discussion
142.

*/*_Which of the following statements regarding two value capacitor motor is incorrect ??

A. It is a reversing motor
B. It is preferred to permanent-split single-value capacitor motor where frequent reversals are required
C. It has low starting as well as rushing currents
D. It has high starting torque
Answer» C. It has low starting as well as rushing currents
Discussion
143.

*/*_The speed of a universal motor is generally reduced by using?

A. gear trains
B. V-belts
C. brakes
D. chains
Answer» B. V-belts
Discussion
144.

*/*_A universal motor is one which?

A. can be operated either on D.C. or A.C. supply at approximately the same speed and output
B. can be marketed internationally
C. runs at dangerously high speed on no-load
D. none of the above
Answer» B. can be marketed internationally
Discussion
145.

*/*_In a capacitor start motor, the phase displacement between starting and running winding can be nearly?

A. 10°
B. 30°
C. 60°
D. 90°
Answer» E.
Discussion
146.

*/*_The range of efficiency for shaded pole motors is?

A. 95% to 99%
B. 80% to 90%
C. 50% to 75%
D. 5% to 35%
Answer» E.
Discussion
147.

*/*_The purpose of stator winding in the compensated repulsion motor is to?

A. provide mechanical balance
B. improve power factor and provide better speed regulation
C. prevent hunting in the motor
D. eliminate armature reaction
Answer» C. prevent hunting in the motor
Discussion
148.

*/*_A single-phase induction motor is?

A. inherently self-starting with high torque
B. inherently self-starting with low torque
C. inherently non-self-starting with low torque
D. inherently non-self-starting with high torque
Answer» D. inherently non-self-starting with high torque
Discussion
149.

*/*_Which of the following motors is used in tape-recorders ??

A. Hysteresis motor
B. Reluctance motor
C. Capacitor-run motor
D. Universal motor
Answer» B. Reluctance motor
Discussion
150.

*/*_Speed torque characteristic of a repulsion induction motor is similar to that of a D.C.?

A. shunt motor
B. series motor
C. compound motor
D. separately excited motor
Answer» D. separately excited motor
Discussion