Explore topic-wise MCQs in Electrical Machines.

This section includes 17 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.

Which one of the following is the base reason to place field on rotor in the alternator?

A. Small power in field circuit
B. Insulation of high voltage is made easy on stator than on rotor
C. Huge power in stator
D. Large current in the stator
Answer» C. Huge power in stator
Discussion
2.

In a salient pole synchronous machine the air gap is least under the middle of the pole shoe and increases outwards.

A. True
B. False
Answer» B. False
Discussion
3.

(i) Transient stability is lower than SSSL. (ii) Transient disturbances are more common.

A. i and ii both are true
B. i false, ii true
C. i true, ii false
D. Both are false
Answer» B. i false, ii true
Discussion
4.

Transient stability limit is less important than SSSL.

A. True
B. False
Answer» C.
Discussion
5.

Series capacitors will improve the ___________

A. SSSL
B. Transient stability
C. Hunting
D. Stiffness
Answer» B. Transient stability
Discussion
6.

The steady state limit can be improved by ___________

A. i, ii, iii
B. i, ii
C. iii only
D. ii, iiiView Answer
Answer» B. i, ii
Discussion
7.

If the load angle is increased till 135°, the consequence will be ___________

A. loss of synchronism
B. no alternation of synchronism
C. increase in stability limit
D. reduction in stability limit
Answer» B. no alternation of synchronism
Discussion
8.

Steady state stability limit is defined as maximum power flow possible through a particular point without loss of stability when the ___________

A. power is increased gradually
B. power is increased suddenly
C. power is reduced gradually
D. power is reduces suddenly
Answer» B. power is increased suddenly
Discussion
9.

WHICH_ONE_OF_THE_FOLLOWING_IS_THE_BASE_REASON_TO_PLACE_FIELD_ON_ROTOR_IN_THE_ALTERNATOR??$

A. Small power in field circuit
B. Insulation of high voltage is made easy on stator than on rotor
C. Huge power in stator
D. Large current in the stator
Answer» C. Huge power in stator
Discussion
10.

If it is planned to bring an incoming alternator to the operating alternator in parallel, then which of the criteria can be ignored?

A. Prime mover speed
B. Voltage magnitude
C. Frequency
D. Phase sequence of the alternator
Answer» B. Voltage magnitude
Discussion
11.

In a salient pole synchronous machine the air gap is least under the middle of the pole shoe and increases outwards?

A. True
B. False
Answer» B. False
Discussion
12.

The supply voltage to an induction motor is decreased by 10%. By what percentage, approximately, will the maximum torque decrease?

A. 5%
B. 10%
C. 20%
D. 40%
Answer» D. 40%
Discussion
13.

(i) Transient stability is lower than SSSL

A. Transient disturbances are more common
B. i and ii both are true
C. i false, ii true
D. i true, ii false
Answer» B. i and ii both are true
Discussion
14.

Transient stability limit is less important than SSSL

A. True
B. False
Answer» C.
Discussion
15.

Series capacitors will improve the

A. SSSL
B. Transient stability
C. Hunting
D. Stiffness
Answer» B. Transient stability
Discussion
16.

If the load angle is increased till 135°, the consequence will be$

A. loss of synchronism
B. no alternation of synchronism
C. increase in stability limit
D. reduction in stability limit
Answer» B. no alternation of synchronism
Discussion
17.

Steady state stability limit is defined as maximum power flow possible through a particular point without loss of stability when

A. power is increased gradually
B. power is increased suddenly
C. power is reduced gradually
D. power is reduces suddenly
Answer» B. power is increased suddenly
Discussion