K-1)The speed of a 3-phase wound-rotor induction motor can be changed by varying the amount of resistance in the rotor circuit. a) true b) false K-2). Which of the following statements are true about a 3-phase synchronous motor? a) It is a constant speed motor even under varying loads. b) It runs at the same speed the magnetic field rotates on the stator. c) It can correct its own, and the supply line's power factor d) all of the above K-3. A) What determines the speed of a 3-phase synchronous motor? a) the number of poles b) the frequency of the supply c) both "a" and "b" d) neither "a" nor "b" K-3)B) From a technician's standpoint, which of the following is the most practical method of providing a wide range of speed control for a 3-phase synchronous motor? a) by changing the frequency b) by changing the number of poles c) both "a" and "b" d) neither "a" nor "b"

K-1)The speed of a 3-phase wound-rotor induction motor can be changed by varying the amount of resistance in the rotor circuit. a) true b) false K-2). Which of the following statements are true about a 3-phase synchronous motor? a) It is a constant speed motor even under varying loads. b) It runs at the same speed the magnetic field rotates on the stator. c) It can correct its own, and the supply line's power factor d) all of the above K-3. A) What determines the speed of a 3-phase synchronous motor? a) the number of poles b) the frequency of the supply c) both "a" and "b" d) neither "a" nor "b" K-3)B) From a technician's standpoint, which of the following is the most practical method of providing a wide range of speed control for a 3-phase synchronous motor? a) by changing the frequency b) by changing the number of poles c) both "a" and "b" d) neither "a" nor "b"

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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