Electrical Engineering Mcqs Practice Test

Question 1

Lap winding is composed of_____________?

Accepted Answer

A. any even number of conductors

Question 2

Satisfactory commutation of D.C. machines requires______________?

Accepted Answer

D. all of the above

Question 3

In a D.C. machine stray loss is the sum of_____________?

Accepted Answer

D. iron loss and mechanical loss

Question 4

The armature core of a D.C. generator is usually made of__________________?

Accepted Answer

A. silicon steel

Question 5

In any rotating machine that part which houses the conductors and in which e.m.f. induced is to be utilized is called____________?

Accepted Answer

D. armature

Question 6

The e.m.f. generated by a shunt wound D.C. generator isE. Now while pole flux remains constant, if the speed of the generator is doubled, the e.m.f. generated will be_______________?

Accepted Answer

B. 2E

Question 7

A D.C. generator can be considered as____________?

Accepted Answer

C. rotating amplifier

Question 8

The voltage drop for which of the following types of brush can be expected to be least ?

Accepted Answer

C. Metal graphite brushes

Question 9

Two generators A and B have 6-poles each. Generator A has wave wound armature while generator B has lap wound armature. The ratio of the induced e.m.f. is generator A and B will be_______________?

Accepted Answer

B. 3 : 1

Question 10

Number of tappings for each equalizer ring is equal to_____________?

Accepted Answer

A. number of pole pairs

Question 11

In D.C. generators, lap winding is used for______________?

Accepted Answer

B. low voltage, high current

Question 12

In a D.C. generator the ripples in the direct e.m.f. generated are reduced by_____________?

Accepted Answer

C. using carbon brushes of superior quality

Question 13

The rapid wear of brushes takes place due to____________?

Accepted Answer

E. all of the above factors

Question 14

Which of the following components of a D.C, generator plays vital role for providing direct current of a D.C. generator ?

Accepted Answer

B. Commutator

Question 15

Compensating windings are used in D.C. generators______________?

Accepted Answer

C. to neutralise the cross-magnetising effect of the armature reaction

Question 16

The following constitute short-circuit in the armature winding.

Accepted Answer

D. All of the above

Question 17

The number of brushes in a commutator depends on______________?

Accepted Answer

D. amount of current to be collected

Question 18

Magnetic field in a D.C. generator is produced by_______________?

Accepted Answer

A. electromagnets

Question 19

To avoid formation of grooves in the commutator of a D.C. machine?

Accepted Answer

A. the brushes of opposite polarity should track each other

Question 20

The demagnetising component of armature reaction in a D.C. generator___________?

Accepted Answer

A. reduces generator e.m.f.