Explore topic-wise MCQs in Electrical Machines.

This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Machines knowledge and support exam preparation. Choose a topic below to get started.

1.

LARGE_SYNCHRONOUS_MACHINES_ARE_CONSTRUCTED_WITH_ARMATURE_WINDING_ON_THE_STATOR_BECAUSE_STATIONARY_ARMATURE_WINDING?$

A. can be insulated satisfactorily for higher voltages
B. can be cooled more efficiently
C. would lead to reduced slip ring losses
D. would have no slot harmonics
Answer» C. would lead to reduced slip ring losses
2.

HOW_MANY_POLES_SHOULD_THE_ALTERNATORS_DRIVEN_BY_THE_OIL_ENGINES_AND_HYDRAULIC_TURBINE_PRIME_MOVERS_MUST_HAVE,_FOR_BETTER_OPERATION??$

A. fewer number of poles
B. larger number of poles
C. medium number of poles
D. any of the mentioned
Answer» C. medium number of poles
3.

What is the equation for frequency of generated EMF?

A. f = PN/120 Hz
B. f = 120/PN Hz
C. f = P/120 Hz
D. f = N/120 Hz
Answer» B. f = 120/PN Hz
4.

In a synchronous machine, salient pole construction has been found to suit best for ___________

A. low speed prime movers
B. high speed prime movers
C. medium speed prime movers
D. any of the mentioned
Answer» B. high speed prime movers
5.

What is the advantage of connecting two coils in parallel?

A. reduce the amount of copper required
B. increase the current per parallel path to double the value
C. increase the voltage capacity
D. all of the mentioned
Answer» C. increase the voltage capacity
6.

The stator frame and end covers in synchronous and induction machines are designed to ___________

A. carry the magnetic flux
B. to serve as a mechanical support
C. to provide cooling or to carry induced EMF
D. any of the mentioned
Answer» C. to provide cooling or to carry induced EMF
7.

What are the advantages of providing the field winding on rotor and armature winding on the stator?

A. more economical
B. more efficient
C. efficient cooling
D. all of the mentioned
Answer» E.
8.

For an induction motor,

A. squirrel cage type is simpler and more economical in construction
B. wound rotor type requires less maintenance
C. squirrel cage type is more rugged and requires less maintenance
D. no external resistance can be inserted in the rotor circuit of squirrel cage induction motor
Answer» D. no external resistance can be inserted in the rotor circuit of squirrel cage induction motor
9.

In which of the following applications, wound rotor type of induction motor is used?

A. where the driven load requires speed control
B. where high starting torque is required
C. when external resistance is to be inserted
D. any of the mentioned
Answer» E.
10.

Which type of slots are used in the construction of large size and small size induction motors respectively?

A. open slots and semiclosed slots
B. semiclosed slots and open slots
C. open slots and open slots
D. semiclosed slots and semiclosed slots
Answer» B. semiclosed slots and open slots