6- In a stepper motor, how is the speed of rotation determined? a) By the current supplied to the motor. b) By the magnitude of the voltage applied. c) By the load applied to the motor. d) By the frequency of the waveforms used. 7- A transformer core is laminated to a) reduce hysteresis loss b) reduce eddy current losses c) reduce copper losses d) reduce all above losses 8- An induction motor with 580 r.p.m. speed at 60 Hz will have a) 8 poles b) 6 poles c) 4 poles d) 2 poles 9- If any two phases for an induction motor are interchanged a) the motor will run in reverse direction b) the motor will run at reduced speed c) the motor will not run d) the motor will burn 10- No-Load speed of which of the following motor will be highest? a) Shunt motor b) Series motor c) Short-Shunt compound motor d) Long-Shunt compound motor

6- In a stepper motor, how is the speed of rotation determined? a) By the current supplied to the motor. b) By the magnitude of the voltage applied. c) By the load applied to the motor. d) By the frequency of the waveforms used. 7- A transformer core is laminated to a) reduce hysteresis loss b) reduce eddy current losses c) reduce copper losses d) reduce all above losses 8- An induction motor with 580 r.p.m. speed at 60 Hz will have a) 8 poles b) 6 poles c) 4 poles d) 2 poles 9- If any two phases for an induction motor are interchanged a) the motor will run in reverse direction b) the motor will run at reduced speed c) the motor will not run d) the motor will burn 10- No-Load speed of which of the following motor will be highest? a) Shunt motor b) Series motor c) Short-Shunt compound motor d) Long-Shunt compound motor

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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