a] Faraday's law of induction states that the emf induced in a loop is directly proportional to the time rate of change of magnetic flux through the loop. b] Lenz's states that the induced currents and induced emf in a conductor are in such a direction as to set-up a magnetic field that opposes the change that produced them. c] A motor contains coil with a total resistance of 15.0 and is supplied by a voltage of 120 V. When the motor is running at its maximum speed, the back emf is 80.0 V. Hence the current in the coil at the instant the motor is turned on is 5.0 A.

a] Faraday's law of induction states that the emf induced in a loop is directly proportional to the time rate of change of magnetic flux through the loop. b] Lenz's states that the induced currents and induced emf in a conductor are in such a direction as to set-up a magnetic field that opposes the change that produced them. c] A motor contains coil with a total resistance of 15.0 and is supplied by a voltage of 120 V. When the motor is running at its maximum speed, the back emf is 80.0 V. Hence the current in the coil at the instant the motor is turned on is 5.0 A.

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter13: Electromagnetic Induction

Section: Chapter Questions

Problem 73AP: A 120-V, series-wound dc motor draws 0.50 A from its power source when operating at full speed, and...

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