Explore topic-wise MCQs in Dc Machines.

This section includes 7 Mcqs, each offering curated multiple-choice questions to sharpen your Dc Machines knowledge and support exam preparation. Choose a topic below to get started.

1.

In DC machines the residual magnetism is present. The order of residual magnetism is ___________

A. 2 to 3 per cent
B. 10 to 15 per cent
C. 20 to 25 per cent
D. 50 to 75 per cent
Answer» B. 10 to 15 per cent
2.

The armature shaft of a DC motor must be able to withstand ______________

A. Bending moment due to weight of the armature.
B. Any unbalanced magnetic pull on the armature core.
C. Twisting stains due to transmission of torque.
D. Bending moment, unbalanced magnetic pull and twisting stains
Answer» E.
3.

Which of the following quantity will decrease if supply voltage is increased?

A. Starting torque
B. Operating speed
C. Full-load current
D. Cannot be determined
Answer» D. Cannot be determined
4.

An electric motor is having constant output power. So, motor will have a torque speed characteristic _______________________

A. Circle about the origin.
B. Straight line parallel to the speed axis.
C. Straight line through the origin.
D. Rectangular hyperbola
Answer» E.
5.

The current drawn by the armature of DC motor is directly proportional to ________________

A. Torque
B. Speed
C. The voltage across the terminals
D. Cannot be determined
Answer» B. Speed
6.

Direction of rotation of motor is determined by ____________

A. Faraday’s law
B. Lenz’s law
C. Coulomb’s law
D. Fleming’s left-hand rule
Answer» E.
7.

Which part will surely tell that given motor is DC motor and not an AC type?

A. Winding
B. Shaft
C. Commutator
D. Stator
Answer» D. Stator