4.1 Which of the following statements about a squirrel cage induction motor is false? (a) It has no external electrical connections to its rotor. (b) A three phase supply is connected to its stator. (c) A magnetic flux which alternates is produced. (d) It is cheap, robust and requires little or skilled maintenance. 4.2 Which of the following statements is false when referring to a three phase induction motor? (a) The synchronous speed is half the supply frequency when it has four poles. (b) In a 2 pole machine, the synchronous speed is equal to the supply frequency. (c) If the number of poles is increased, the synchronous speed is reduced. (d) The synchronous speed is inversely proportional to the number of pole.

4.1 Which of the following statements about a squirrel cage induction motor is false? (a) It has no external electrical connections to its rotor. (b) A three phase supply is connected to its stator. (c) A magnetic flux which alternates is produced. (d) It is cheap, robust and requires little or skilled maintenance. 4.2 Which of the following statements is false when referring to a three phase induction motor? (a) The synchronous speed is half the supply frequency when it has four poles. (b) In a 2 pole machine, the synchronous speed is equal to the supply frequency. (c) If the number of poles is increased, the synchronous speed is reduced. (d) The synchronous speed is inversely proportional to the number of pole.

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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