1. Each of the following statements regarding stator flux of an induction motor is true EXCEPT a. it is constant in magnitude speed b. it induces emf in the rotor bars c. it revolves around the stator at synchronous d. its magnitude depends on the motor load 2. Two of the power supply terminals to a 3-phase induction motor got interchanged during reconnection after maintenance. When put back into service, the motor will. a. fail to rotate b. rotate in opposite direction as it was c. rotate in the same direction as it was d. burn out 3. A 3-phase, 60 hz induction motor has full load speed of 1140 rpm. For this motor, the speed of stator field with respect for revolving rotor structures will be a. 1,560 rpm b. 1,440 rpm c. 1,500 rpm d. 60 rpm

1. Each of the following statements regarding stator flux of an induction motor is true EXCEPT a. it is constant in magnitude speed b. it induces emf in the rotor bars c. it revolves around the stator at synchronous d. its magnitude depends on the motor load 2. Two of the power supply terminals to a 3-phase induction motor got interchanged during reconnection after maintenance. When put back into service, the motor will. a. fail to rotate b. rotate in opposite direction as it was c. rotate in the same direction as it was d. burn out 3. A 3-phase, 60 hz induction motor has full load speed of 1140 rpm. For this motor, the speed of stator field with respect for revolving rotor structures will be a. 1,560 rpm b. 1,440 rpm c. 1,500 rpm d. 60 rpm

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter35: Harmonics 916

Section: Chapter Questions

Problem 3RQ: Would a positive-rotating harmonic or a negative-rotating harmonic be more harmful to an induction...

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