Explore topic-wise MCQs in Design Electrical Machines.

This section includes 15 Mcqs, each offering curated multiple-choice questions to sharpen your Design Electrical Machines knowledge and support exam preparation. Choose a topic below to get started.

1.

What is the formula for the outer diameter of the stator?

A. outer diameter = inner diameter + depth of the slots + depth of armature core
B. outer diameter = inner diameter + 2*depth of the slots + depth of armature core
C. outer diameter = inner diameter + 2*(depth of the slots + depth of armature core)
D. outer diameter = inner diameter + depth of the slots + 2*depth of armature core
E. outer diameter = inner diameter + depth of the slots + 2*depth of armature core
Answer» D. outer diameter = inner diameter + depth of the slots + 2*depth of armature core
Discussion
2.

What is the formula for the depth of armature core?

A. depth of armature core = flux / length of the iron core * flux density
B. depth of armature core = flux * length of the iron core * flux density
C. depth of armature core = flux / 2 * length of the iron core * flux density
D. depth of armature core = flux * 2 * length of the iron core * flux density
Answer» D. depth of armature core = flux * 2 * length of the iron core * flux density
Discussion
3.

The flux density in the armature core of salient pole machines lies between 1-1.2 Wb per m2.

A. true
B. false
Answer» B. false
Discussion
4.

What is the formula for the minimum width of the tooth?

A. minimum width of tooth = flux * pole proportion * (number of stator slots / number of poles) * length * 1.8
B. minimum width of tooth = flux / pole proportion * (number of stator slots / number of poles) * length * 1.8
C. minimum width of tooth = flux * pole proportion / (number of stator slots / number of poles) * length * 1.8
D. minimum width of tooth = flux * pole proportion * (number of stator slots / number of poles) * length / 1.8
Answer» C. minimum width of tooth = flux * pole proportion / (number of stator slots / number of poles) * length * 1.8
Discussion
5.

THE_FLUX_DENSITY_IN_THE_ARMATURE_CORE_OF_SALIENT_POLE_MACHINES_LIES_BETWEEN_1-1.2_WB_PER_M2??$

A. true
B. false
Answer» B. false
Discussion
6.

What is the formula for the outer diameter of the stator?$

A. outer diameter = inner diameter + depth of the slots + depth of armature core
B. outer diameter = inner diameter + 2*depth of the slots + depth of armature core
C. outer diameter = inner diameter + 2*(depth of the slots + depth of armature core)
D. outer diameter = inner diameter + depth of the slots + 2*depth of armature core
Answer» D. outer diameter = inner diameter + depth of the slots + 2*depth of armature core
Discussion
7.

What_is_the_formula_for_the_depth_of_armature_core?$

A. depth of armature core = flux / length of the iron core * flux density
B. depth of armature core = flux * length of the iron core * flux density
C. depth of armature core = flux / 2 * length of the iron core * flux density
D. depth of armature core = flux * 2 * length of the iron core * flux density
Answer» D. depth of armature core = flux * 2 * length of the iron core * flux density
Discussion
8.

What is the formula for the height of length of mean turn of armature?

A. length of mean turn = 2*length + 2.5*pole pitch + 0.06 kV + 0.2
B. length of mean turn = 2*length + 2*pole pitch + 0.06 kV + 0.2
C. length of mean turn = 2*length + 2.5*pole pitch – 0.06 kV – 0.2
D. length of mean turn = 2*length – 2.5*pole pitch – 0.06 kV – 0.2
Answer» B. length of mean turn = 2*length + 2*pole pitch + 0.06 kV + 0.2
Discussion
9.

Why are slot made deeper in the machine?

A. to increase the short circuit current
B. to reduce the short circuit current
C. to increase the open circuit current
D. to reduce the open circuit current
Answer» C. to increase the open circuit current
Discussion
10.

By how much should the depth of slot not exceed the width?

A. two times
B. three times
C. four times
D. six times
Answer» C. four times
Discussion
11.

What is the formula for the maximum permissible width of slot?

A. maximum permissible width = slot pitch * minimum width of the teeth
B. maximum permissible width = slot pitch + minimum width of the teeth
C. maximum permissible width = slot pitch / minimum width of the teeth
D. maximum permissible width = slot pitch – minimum width of the teeth
Answer» E.
Discussion
12.

How is the teeth and the minimum width designed in the machines?

A. teeth is tapered and minimum width is across the medium
B. teeth is sharpened and minimum width occurs across the air gap
C. teeth is widened and minimum width occurs across the air gap
D. teeth is reduced and minimum width occurs across the medium
Answer» B. teeth is sharpened and minimum width occurs across the air gap
Discussion
13.

Name the slots that are commonly used.

A. parallel sided
B. square sided
C. rectangular
D. circular
Answer» B. square sided
Discussion
14.

What is the formula for the minimum width of tooth?

A. minimum width of tooth = flux * pole proportion * (number of stator slots / number of poles) * length * 1.8
B. minimum width of tooth = flux / pole proportion * (number of stator slots / number of poles) * length * 1.8
C. minimum width of tooth = flux * pole proportion / (number of stator slots / number of poles) * length * 1.8
D. minimum width of tooth = flux * pole proportion * (number of stator slots / number of poles) * length / 1.8
Answer» C. minimum width of tooth = flux * pole proportion / (number of stator slots / number of poles) * length * 1.8
Discussion
15.

What is the range of the flux density in the teeth at no load?

A. 1.7-1.8 Wb per mm<sup>2</sup>
B. 1.3-1.5 Wb per mm<sup>2</sup>
C. 1.3-1.6 Wb per mm<sup>2</sup>
D. 1.4-1.6 Wb per mm<sup>2</sup>
Answer» B. 1.3-1.5 Wb per mm<sup>2</sup>
Discussion