8. A three-phase, 50 Hz, four-pole induction motor has a slip of 4%. Determine (a) speed of the motor, and (b) frequency of rotor emf (c) if the rotor has a resistance of 12 and standstill reactance of 4 $2, calculate power factor (a) at standstill, and (b) at a speed of 1400 rpm.

8. A three-phase, 50 Hz, four-pole induction motor has a slip of 4%. Determine (a) speed of the motor, and (b) frequency of rotor emf (c) if the rotor has a resistance of 12 and standstill reactance of 4 $2, calculate power factor (a) at standstill, and (b) at a speed of 1400 rpm.

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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Concept explainers

Three Phase Induction Motor

The induction motor is an electric motor that runs on AC (alternating current) and it is of two type single phase motor that work on single-phase power supply and three-phase motor that work on three-phase power supply.

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8. A three-phase, 50 Hz, four-pole induction motor has a slip of 4%. Determine (a) speed of the motor,
and (b) frequency of rotor emf (c) if the rotor has a resistance of 12 and standstill reactance of 4 $2,
calculate power factor (a) at standstill, and (b) at a speed of 1400 rpm.

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