1000+ DC Generators Objective Questions and Answers Pdf - 3

Question: 11

If a speed of a dc motor increases with load torque, then it is a

(A) cumulatively compounded motor

(B) differentially compounded motor

(C) permanent magnet

(D) series motor

Question: 12

The commutator of a dc motor serves the purpose of

(A) avoiding arc at the brushes

(B) changing ac to dc

(C) converting dc into ac

(D) reducing friction

Question: 13

The torque speed characteristic of a dc shunt motor is

(A) a drooping straight line

(B) a parabola

(C) a rectangular hyperbola

(D) none of these

Question: 14

The principle of dynamically induced emf is utilised in

(A) Choke

(B) Generator

(C) Thermocouple

(D) Transformer

Question: 15

The air gap between the yoke and armature in a dc motor is kept small

(A) to avoid transverse motion

(B) to avoid locking of the armature

(C) to avoid overheating of the machine

(D) to achieve a stronger magnetic field