Conceptual Physics (12th Edition)

Published by Addison-Wesley
ISBN 10: 0321909100
ISBN 13: 978-0-32190-910-7

Chapter 25 - Think and Discuss - Page 483: 89

Answer

See below.

Work Step by Step

The windings of the electric motor draw a small current when the motor is operating. Two sources of this current must be addressed. First is the current input into the windings that turns the armature (the motor effect). Second, the rotation of the windings in the magnetic field of the motors induces an oppositely directed current (the generator effect). That means that the net current is small. When the motor suddenly jams and the armature stops rotating, the net current spikes upward because the second contribution, the generated current, suddenly disappears. This can overheat the motor.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.