Question 1

Which type of load is offered by cranes and hoists ?

Accepted Answer

A) Gradually varying load 
B) Non-reversing, no-load start 
C) Reversing, light start 
D) Reversing, heavy start 
A) Gradually varying load 
B) Non-reversing, no-load start 
C) Reversing, light start 
D) Reversing, heavy start D

Question 2

If the centrifugal switch does not open at 70 to 80 percent of synchronous speed of motor, it would result in

Accepted Answer

A) damage to the starting winding 
B) damage to the centrifugal switch 
C) overloading of running winding 
D) none of the above 
A) damage to the starting winding 
B) damage to the centrifugal switch 
C) overloading of running winding 
D) none of the above A

Question 3

The speed control of universal motor used for sewing machines is by

Accepted Answer

A) friction 
B) varying the resistance 
C) tapping the field 
D) centrifugal mechanism 
A) friction 
B) varying the resistance 
C) tapping the field 
D) centrifugal mechanism B

Question 4

In repulsion motor, maximum torque is developed when

Accepted Answer

A) brush axis is at 45° electrical to the field axis 
B) brush axis coincides with the field axis 
C) brush axis is at 90° electrical to the field axis 
D) none of the above 
A) brush axis is at 45° electrical to the field axis 
B) brush axis coincides with the field axis 
C) brush axis is at 90° electrical to the field axis 
D) none of the above

Question 5

In a ceilingfan employing capacitor run motor

Accepted Answer

A) secondary winding surrounds the primary winding 
B) primary winding surrounds the secondary winding 
C) both are usual arrangements 
D) none of the above 
A) secondary winding surrounds the primary winding 
B) primary winding surrounds the secondary winding 
C) both are usual arrangements 
D) none of the above

Question 6

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

Accepted Answer

A) armature winding 
B) field winding 
C) either armature winding or field winding 
D) none of the above 
A) armature winding 
B) field winding 
C) either armature winding or field winding 
D) none of the above

Question 7

Which motor is normally free from mechanical and magnetic vibrations ?

Accepted Answer

A) Split phase motor 
B) Universal motor 
C) Hysteresis motor 
D) Shaded pole motor 
A) Split phase motor 
B) Universal motor 
C) Hysteresis motor 
D) Shaded pole motor

Question 8

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

Accepted Answer

A) Capacitor run motor 
B) Shaded pole motor 
C) Hysteresis motor 
D) Schrage motor 
A) Capacitor run motor 
B) Shaded pole motor 
C) Hysteresis motor 
D) Schrage motor

Question 9

The speed/load characteristics of a universal motor is same as that of

Accepted Answer

A) A.C. motor 
B) D.C. shunt motor 
C) D.C. series motor 
D) none of the above 
A) A.C. motor 
B) D.C. shunt motor 
C) D.C. series motor 
D) none of the above

Question 10

A reluctance motor

Accepted Answer

A) is self-starting 
B) is constant speed motor 
C) needs no D.C. excitation 
D) all of the above 
A) is self-starting 
B) is constant speed motor 
C) needs no D.C. excitation 
D) all of the above

Question 11

The speed of a universal motor is generally reduced by using

Accepted Answer

A) gear trains 
B) V-belts 
C) brakes 
D) chains 
A) gear trains 
B) V-belts 
C) brakes 
D) chains

Question 12

Which of the following applications always have some load whenever switched on ?

Accepted Answer

A) Vacuum cleaners 
B) Fan motors 
C) Pistol drills 
D) All of the above 
A) Vacuum cleaners 
B) Fan motors 
C) Pistol drills 
D) All of the above

Question 13

In split phase motor main winding is of

Accepted Answer

A) thin wire placed at the top of the slots 
B) thin wire placed at the bottom of the slots 
C) thick wire placed at the bottom of the slots 
D) thick wire placed at the top of the" slots 
A) thin wire placed at the top of the slots 
B) thin wire placed at the bottom of the slots 
C) thick wire placed at the bottom of the slots 
D) thick wire placed at the top of the" slots

Question 14

The electric motor used in portable drills is

Accepted Answer

A) capacitor run motor 
B) hysteresis motor 
C) universal motor 
D) repulsion motor 
A) capacitor run motor 
B) hysteresis motor 
C) universal motor 
D) repulsion motor

Question 15

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

Accepted Answer

A) Universal motor 
B) Repulsion motor 
C) Capacitor motor 
D) All single phase motors have zero starting torque 
A) Universal motor 
B) Repulsion motor 
C) Capacitor motor 
D) All single phase motors have zero starting torque

Question 16

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

Accepted Answer

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 
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

Question 17

The shaded pole motor is used for

Accepted Answer

A) high starting torque 
B) low starting torque 
C) medium starting torque 
D) very high starting torque 
A) high starting torque 
B) low starting torque 
C) medium starting torque 
D) very high starting torque

Question 18

The rotor slots, in an induction motor, are usually not quite parallel to the shaft because it

Accepted Answer

A) improves the efficiency 
B) helps the rotor teeth to remain under the stator teeth 
C) helps in reducing the tendency of the rotor teeth to remain under the stator teeth 
D) improves the power factor 
A) improves the efficiency 
B) helps the rotor teeth to remain under the stator teeth 
C) helps in reducing the tendency of the rotor teeth to remain under the stator teeth 
D) improves the power factor

Question 19

As hysteresis motors are free from mechanical and magnetic vibrations therefore these are considered as suitable for

Accepted Answer

A) fans 
B) blowers 
C) sound equipment 
D) mixer grinders 
A) fans 
B) blowers 
C) sound equipment 
D) mixer grinders

Question 20

Speed torque characteristic of a repulsion induction motor is similar to that of a D.C.

Accepted Answer

A) shunt motor 
B) series motor 
C) compound motor 
D) separately excited motor 
A) shunt motor 
B) series motor 
C) compound motor 
D) separately excited motor

Which type of load is offered by cranes and hoists ?

If the centrifugal switch does not open at 70 to 80 percent of synchronous speed of motor, it would result in

The speed control of universal motor used for sewing machines is by

In repulsion motor, maximum torque is developed when

In a ceilingfan employing capacitor run motor

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

Which motor is normally free from mechanical and magnetic vibrations ?

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

The speed/load characteristics of a universal motor is same as that of

A reluctance motor

The speed of a universal motor is generally reduced by using

Which of the following applications always have some load whenever switched on ?

In split phase motor main winding is of

The electric motor used in portable drills is

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

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

The shaded pole motor is used for

The rotor slots, in an induction motor, are usually not quite parallel to the shaft because it

As hysteresis motors are free from mechanical and magnetic vibrations therefore these are considered as suitable for

Speed torque characteristic of a repulsion induction motor is similar to that of a D.C.

Single-Phase Motor

Motor Types and Applications

Motor Types and Applications

Single-Phase Induction Motors and Their Features

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Exam 3: Electric Motors and Their Characteristics

Which type of load is offered by cranes and hoists ?

If the centrifugal switch does not open at 70 to 80 percent of synchronous speed of motor, it would result in

The speed control of universal motor used for sewing machines is by

In repulsion motor, maximum torque is developed when

In a ceilingfan employing capacitor run motor

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

Which motor is normally free from mechanical and magnetic vibrations ?

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

The speed/load characteristics of a universal motor is same as that of

A reluctance motor

The speed of a universal motor is generally reduced by using

Which of the following applications always have some load whenever switched on ?

In split phase motor main winding is of

The electric motor used in portable drills is

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

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

The shaded pole motor is used for

The rotor slots, in an induction motor, are usually not quite parallel to the shaft because it

As hysteresis motors are free from mechanical and magnetic vibrations therefore these are considered as suitable for

Speed torque characteristic of a repulsion induction motor is similar to that of a D.C.

Single-Phase Motor

Motor Types and Applications

Motor Types and Applications

Single-Phase Induction Motors and Their Features

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