Explore topic-wise MCQs in Electric Drives.

This section includes 9 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.

250V, 15A, 1100 rpm separately excited dc motor with armature resistance (Ra) equal to 2 ohms. Calculate back emf developed in the motor when it operates on half of the full load. (Assume rotational losses are neglected)

A. 210V
B. 240V
C. 230V
D. 235V
Answer» E.
Discussion
2.

Torque is a scalar quantity.

A. True
B. False
Answer» C.
Discussion
3.

If the starting torque of the motor is less than the load torque, the motor will fail to start.

A. True
B. False
Answer» B. False
Discussion
4.

Buck converter is used to _________

A. Step down the voltage
B. Step up the voltage
C. Equalize the voltage
D. Step up and step down the voltage
Answer» B. Step up the voltage
Discussion
5.

What is the dimensional formula for torque?

A. [ML<sup>2</sup>T<sup>-2</sup>]
B. [MLT<sup>-2</sup>]
C. [M<sup>1</sup>L<sup>2</sup>T<sup>-3</sup>]
D. [LT<sup>-2</sup>]
Answer» B. [MLT<sup>-2</sup>]
Discussion
6.

Calculate the value of the torque when 10 N force is applied perpendicular to a 10 m length of rod fixed at the center.

A. 200 N-m
B. 300 N-m
C. 100 N-m
D. 400 N-m
Answer» C. 100 N-m
Discussion
7.

The unit of the torque is ______

A. N-m
B. N-m<sup>2</sup>
C. N-m/sec
D. N-Hz
Answer» B. N-m<sup>2</sup>
Discussion
8.

Force resisting the upward motion of a body on an inclined plane is given by (alpha the angle of inclination, W- the weight of the body).

A. F = W sin(alpha)
B. F = W cosec(alpha)
C. F = W sec(alpha)
D. F = W cos(alpha)
Answer» B. F = W cosec(alpha)
Discussion
9.

What is the empirical formula for the tractive force required to overcome curve resistance? (W-the weight of the body, R radius of curvature)

A. 710 W R
B. 700 W R
C. 720 W R
D. 750 W R
Answer» C. 720 W R
Discussion