only question c (a) What is back emf of a dc motor? What are the factors controlling motor speed? Draw thespeed-torque characteristics of a de series motor.(b) Explain the working principle of an induction motor. Show that the slip of an induction motoris equal to 1 at stationary.(c) Briefly explain the operation of an alternator. A 440 V, shunt motor has armature resistanceof 0.8 2 and field resistance of 200 N. Determine the back emf when giving an output of7460 watt at 85 percent efficiency.

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(c) Briefly explain the operation of an alternator. A 440 V, shunt motor has armature resistance of 0.8 2 and field resistance of 200 2. Determine the back emf when giving an output of 7460 watt at 85 percent efficiency.

(c) Briefly explain the operation of an alternator. A 440 V, shunt motor has armature resistance of 0.8 2 and field resistance of 200 2. Determine the back emf when giving an output of 7460 watt at 85 percent efficiency.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

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