A motor is designed to operate on 117 V and draws a current of 9.39 A when it first starts up. At its normal operating speed, the motor draws a current of 1.73 A. Obtain (a) the resistance of the armature coil, (b) the back emf developed at normal speed, and (c) the current drawn by the motor at one-third normal speed.

A motor is designed to operate on 117 V and draws a current of 9.39 A when it first starts up. At its normal operating speed, the motor draws a current of 1.73 A. Obtain (a) the resistance of the armature coil, (b) the back emf developed at normal speed, and (c) the current drawn by the motor at one-third normal speed.

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter23: Faraday’s Law And Inductance

Section: Chapter Questions

Problem 72P

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