1000+ Electrical Machines Questions and Answers Pdf - 1

Question: 1

Speed of universal motor is

(A) inversely proportional to frequency of supply

(B) independently of frequency of supply

(C) proportional to square of frequency of supply

(D) proportional to frequency of supply

Question: 2

A 3 phase induction requires starter

(A) because there is no back emf induced in the stator winding during starting

(B) because the induced secondary voltage and hence the currents in the windings are abnormally high during starting

(C) to increase the starting torque

(D) because the motor does not possess an inherent starting torque

Question: 3

Counter emf of a DC motor

(A) regulates its armature voltage

(B) helps in energy conversion

(C) aids applied voltage

(D) exceeds supply voltage

Question: 4

Rotating part of DC motor is known as

(A) armature

(B) starter

(C) carbon brush

(D) pole

Question: 5

Generators work on the principle of production of

(A) dynamically induced emf

(B) statically induced emf

(C) dynamically and statically induced emf

(D) none of the above