In an induction motor slip will be negative when the _________ a) rotor rotates at speed more than synchronous speed and in the direction of the rotation of stator field b) stator magnetic field and rotor rotate in opposite direction c) rotor rotates at speed less than synchronous speed and in the opposite direction of the rotation of stator field d) rotor rotates at speed more than synchronous speed and in the opposite direction of the rotation of stator field

In an induction motor slip will be negative when the _________ a) rotor rotates at speed more than synchronous speed and in the direction of the rotation of stator field b) stator magnetic field and rotor rotate in opposite direction c) rotor rotates at speed less than synchronous speed and in the opposite direction of the rotation of stator field d) rotor rotates at speed more than synchronous speed and in the opposite direction of the rotation of stator field

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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This question refers to a three-phase induction motor. which statement are false (A) The slip speed is the synchronous speed minus the rotor speed. (B) As the rotor speed is loaded, the slip decreases. (C) The frequency of induced rotor EMF's increases with load on the rotor (D) The toque on the rotor is due to the interaction of magnetic fields.
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