Explore topic-wise MCQs in Electric Drives.

This section includes 13 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 2 Ω resistor with 8 A current flowing through it.

A. 125 W
B. 128 W
C. 123 W
D. 126 W
Answer» C. 123 W
2.

Calculate the value of the frequency if the inductive reactance is 72 Ω and the value of the inductor is 7 H.

A. 1.63 Hz
B. 1.54 Hz
C. 1.78 Hz
D. 1.32 Hz
Answer» B. 1.54 Hz
3.

Calculate the reactive power in a 45 Ω resistor with 1.78 A current flowing through it.

A. 28.8 VAR
B. 23.4 VAR
C. 25.82 VAR
D. 0 VAR
Answer» E.
4.

Calculate the active power in a 9.854 H inductor.

A. 4.98 W
B. 0 W
C. 8.59 W
D. 1 W
Answer» C. 8.59 W
5.

A 3-phase induction motor runs at almost 70 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. 30 revolution per minute
C. 40 revolution per minute
D. 50 revolution per minute
Answer» B. 30 revolution per minute
6.

Calculate the velocity of the satellite if the angular speed is 87 rad/s and radius is 7.4 m.

A. 643.8 m/s
B. 642.4 m/s
C. 641.9 m/s
D. 643.2 m/s
Answer» B. 642.4 m/s
7.

The slope of the V-I curve is 4.9°. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.

A. .03 Ω
B. .08 Ω
C. .04 Ω
D. .07 Ω
Answer» C. .04 Ω
8.

Armature reaction is magnetizing in nature due to a purely resistive load in the synchronous generator.

A. True
B. False
Answer» C.
9.

A particular voltage is made up of two components: a 5 A and a cosine wave of peak value 7.8 A. The average value of voltage is _________

A. Zero
B. 35.14 A
C. 78 A
D. 5 A
Answer» E.
10.

Calculate the moment of inertia of the satellite having a mass of 79 kg and diameter of 83 cm.

A. 13.65 kgm2
B. 13.60 kgm2
C. 12.67 kgm2
D. 13.82 kgm2
Answer» C. 12.67 kgm2
11.

Calculate the phase angle of the sinusoidal waveform i(t)=sin(.6πt+π÷.88).

A. 100π÷88
B. 100π÷8
C. 100π÷8
D. π÷88
Answer» B. 100π÷8
12.

A 38-pole, 3-phase, 80 Hz induction motor is operating at a speed of 12 rpm. The frequency of the rotor current of the motor in Hz is __________

A. 75.2
B. 76.1
C. 79.2
D. 79.6
Answer» C. 79.2
13.

A particular current is made up of two components: a 10 A and a sine wave of peak value 14.14 A. The average value of current is _________

A. Zero
B. 24.14 A
C. 10 A
D. 14.14 A
Answer» D. 14.14 A