Electrical Machine - II (3150910) MCQs

MCQs of Induction Machines

Showing 11 to 20 out of 95 Questions
11.

What is the Speed of Rotating magnetic field (r.m.f) Øs produced in the stator?

(a)

Variable Speed

(b)

Synchronous Speed

(c)

Asynchronous Speed

(d)

Depends on Load

Answer:

Option (b)

12.

The Induction motor is known as _______________ motor

(a)

Singly Excited

(b)

Doubly Excited

(c)

excitation less

(d)

Self Excited

Answer:

Option (a)

13.

Flux produced in the rotor of the three-phase induction motor is due to 

(a)

Induction principle

(b)

conduction principle

(c)

PM principle

(d)

Lorenz low 

Answer:

Option (a)

14.

Rotor rotate in which direction in a three-phase induction motor?

(a)

In the clockwise direction only

(b)

in the direction of RMF

(c)

In the anticlockwise direction only

(d)

Can't say. Depends on Load

Answer:

Option (b)

15.

What is the basic difference between stator & rotor core of three-phase induction motor?

(a)

No difference

(b)

The stator core has a slot on its outer periphery and rotor core has slot on its inner periphery

(c)

The stator core has a slot on its inner periphery and rotor core has a slot on its outer periphery

(d)

only size difference

Answer:

Option (c)

16.

What is the reason for Skew Slot in a rotor of a three-phase induction motor?

(a)

reducing magnetic humming

(b)

decrease slot harmonics

(c)

avoid the locking tendency

(d)

All of these 

Answer:

Option (d)

17.

What is the role of End Ring or Slip Ring (with brushes) in the rotor circuit of three-phase induction machine?

(a)

to close the rotor circuit.

(b)

all of these 

(c)

to balance the rotor while its in rotation

(d)

to reduced harmonic

Answer:

Option (a)

18.

Which of the following motor has simplest and rugged construction?

(a)

Squirrel Cage Motor (Three-phase induction motor)

(b)

Wound Rotor Motor (Three-phase induction motor)

(c)

Synchronous Motor 

(d)

DC Motor 

Answer:

Option (a)

19.

What are the advantages of Slip ring induction motor compare to the squirrel cage induction motor?

(a)

Can produce variable starting and running torque

(b)

Can limit starting current

(c)

Slip power recovery is possible

(d)

All of these 

Answer:

Option (d)

20.

What are the advantages of  Squirrel cage induction motor compare to the Slip ring induction motor?

(a)

high efficiency and low maintenance 

(b)

simplest and rugged construction

(c)

no issue of sparking in the rotor circuit 

(d)

All of these 

Answer:

Option (d)

Showing 11 to 20 out of 95 Questions