Explore topic-wise MCQs in Electric Drives.

This section includes 14 Mcqs, each offering curated multiple-choice questions to sharpen your Electric Drives knowledge and support exam preparation. Choose a topic below to get started.

1.

Calculate the active power in a .56 F capacitor.

A. 37.8 W
B. 0 W
C. 15.4 W
D. 124.5 W
Answer» C. 15.4 W
2.

The unit of angular frequency is Hz.

A. True
B. False
Answer» B. False
3.

Calculate the active power in a .8 resistor with 2 A current flowing through it.

A. 2.4 W
B. 3.4 W
C. 2.2 W
D. 3.2 W
Answer» E.
4.

Calculate the active power in a .7889 H inductor.

A. .123 W
B. .155 W
C. 0 W
D. .487 W
Answer» D. .487 W
5.

A 3-phase induction motor runs at almost 140 rpm at no load and 50 rpm at full load when supplied with power from a 50 Hz, 3-phase supply. What is the corresponding speed of the rotor field with respect to the rotor?

A. 20 revolution per minute
B. 80 revolution per minute
C. 90 revolution per minute
D. 70 revolution per minute
Answer» D. 70 revolution per minute
6.

Calculate the value of the torque when 1 N force is applied perpendicular to a 1 m length of chain fixed at the center.

A. 1 N-m
B. 3 N-m
C. 2 N-m
D. 4 N-m
Answer» B. 3 N-m
7.

The slope of the V-I curve is 16.8 . Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.

A. .324
B. .301
C. .343
D. .398
Answer» C. .343
8.

100 V, 2 A, 90 rpm separately excited dc motor with armature resistance (Ra) equal to 8 ohms. Calculate back emf developed in the motor when it operates on 3th/4 of the full load. (Assume rotational losses are neglected)

A. 100 V
B. 87 V
C. 88 V
D. 90 V
Answer» D. 90 V
9.

Calculate the value of the torque when 89 N force is applied perpendicular to a 78 m length of stick fixed at the center.

A. 6942 N-m
B. 3000 N-m
C. 1000 N-m
D. 4470 N-m
Answer» B. 3000 N-m
10.

Calculate the moment of inertia of the thin spherical shell having a mass of 703 kg and diameter of 376 cm.

A. 1639.89 kgm<sup>2</sup>
B. 1628.47 kgm<sup>2</sup>
C. 1678.12 kgm<sup>2</sup>
D. 1978.19 kgm<sup>2</sup>
Answer» B. 1628.47 kgm<sup>2</sup>
11.

Calculate the moment of inertia of the disc having a mass of 4 kg and diameter of 1458 cm.

A. 106.288 kgm<sup>2</sup>
B. 104.589 kgm<sup>2</sup>
C. 105.487 kgm<sup>2</sup>
D. 107.018 kgm<sup>2</sup>
Answer» B. 104.589 kgm<sup>2</sup>
12.

Calculate the phase angle of the sinusoidal waveform z(t)=.99sin(4578 t+78 78).

A. 3
B. 2
C. 7
D.
Answer» E.
13.

A 10-pole, 3-phase, 60 Hz induction motor is operating at a speed of 100 rpm. The frequency of the rotor current of the motor in Hz is __________

A. 52.4
B. 54.8
C. 51.66
D. 51.77
Answer» D. 51.77
14.

Calculate the active power in a .45 H inductor.

A. 0.11 W
B. 0.14 W
C. 0.15 W
D. 0 W
Answer» E.