A motor in normal operation carries a direct current of 0.840 A when connected to a 120 V power supply. The resistance in the motor windings is 19.2 2. Determine the following values. (a) While in normal operation, what is the back emf generated by the motor? (b) While in normal operation, at what rate is internal energy produced in the windings? w (c) What If? Suppose that a malfunction stops the motor shaft from rotating. At what rate will internal energy be produced in the windings in this case? (Most motors have a thermal switch that will turn off the motor to prevent overheating when this occurs.) kw Additional Materials

A motor in normal operation carries a direct current of 0.840 A when connected to a 120 V power supply. The resistance in the motor windings is 19.2 2. Determine the following values. (a) While in normal operation, what is the back emf generated by the motor? (b) While in normal operation, at what rate is internal energy produced in the windings? w (c) What If? Suppose that a malfunction stops the motor shaft from rotating. At what rate will internal energy be produced in the windings in this case? (Most motors have a thermal switch that will turn off the motor to prevent overheating when this occurs.) kw Additional Materials

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter31: Faraday’s Law

Section: Chapter Questions

Problem 31.48P: A motor in normal operation carries a direct current of 0.850 A when connected to a 120-V power...

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