Explore topic-wise MCQs in Electrical Machines.

This section includes 11 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.

IN_A_4_POLE_MACHINE,_WHAT_IS_THE_FLUX_PER_POLE_PRODUCED,_IF_THE_ARMATURE_LENGTH_IS_L_AND_RADIUS_IS_R_AND_BP_IS_PEAK_VALUE_OF_SINUSOIDAL_FLUX??$

A. 4B<sub>p</sub>lr
B. 2B<sub>p</sub>lr
C. B<sub>p</sub>lr
D. B<sub>p</sub>lr/2
Answer» D. B<sub>p</sub>lr/2
2.

The equation for flux per pole Φ=4/PBplr, is valid for _____________$#

A. for salient pole rotor only
B. for cylindrical pole rotor only
C. for both cylindrical and salient pole rotor
D. none of the mentioned
Answer» D. none of the mentioned
3.

If Bp= peak value of sinusoidal flux density wave, L = armature core length, D = armature diameter, P = number of poles, the?

A. flux per pole, Φ=2/PB<sub>p</sub>LD
B. Average flux density, B<sub>av</sub>=2/πB<sub>p</sub>
C. Φ=4/PB<sub>p</sub>LD
D. B<sub>av</sub>=3/πB<sub>p</sub>
Answer» B. Average flux density, B<sub>av</sub>=2/‚âà√¨‚àö√ëB<sub>p</sub>
4.

A chording angle ε is defined as the angle by which coil span departs from __________$

A. 90° electrical space degrees
B. 180° electrical space degrees
C. 360° electrical space degrees
D. any of the mentioned
Answer» C. 360¬¨¬®‚Äö√†√ª electrical space degrees
5.

In a full pitch coil, the two coil sides are how many electrical space degrees apart?

A. 180 electrical degrees
B. 90 electrical degrees
C. 45 electrical degrees
D. none of the mentioned
Answer» B. 90 electrical degrees
6.

One turn consists of _____________

A. two coil sides
B. two conductors
C. four conductors
D. four coil sides
Answer» C. four conductors
7.

A coil consists of _____________

A. two conductors
B. two coil sides
C. two turns
D. four turns
Answer» C. two turns
8.

The part of the coil in which EMF is generated is known as _____________

A. end connection
B. coil sides
C. coil span
D. none of the mentioned
Answer» C. coil span
9.

A pole pitch in electrical machine _____________

A. = 180° electrical
B. = 180° mechanical
C. > 180° electrical
D. < 180° electrical
Answer» B. = 180¬¨¬®‚Äö√†√ª mechanical
10.

What is the relation between ‘ω’, angular speed in electrical radians per second and ‘ωm‘, angular speed in mechanical radians per second, for a P-pole machine?$

A. ω = 2/Pω<sub>m</sub>
B. ω = 4/Pω<sub>m</sub>
C. ω<sub>m</sub> = P/2ω
D. ω = P/2ω<sub>m</sub>
Answer» E.
11.

For a P-pole machine, the relation between electrical and mechanical degrees is given by _____________

A. θ<sub>elec</sub> = 2/P θ<sub>mech</sub>
B. θ<sub>elec</sub> = 4/P θ<sub>mech</sub>
C. θ<sub>mech</sub> = P/2 θ<sub>elec</sub>
D. θ<sub>elec</sub> = P/2 θ<sub>mech</sub>
Answer» E.