4. The speed of a 50 hz, 4 pole induction motor running with a slip of 54 will be a. 1760 rpm b. 950 rpm c. 1488 rpm d. 1425 rpm 5. A 3-phase induction motor is rated 220 volts and 1745 rpm and 784 power factor. What is the percent slip? (EE board Prob. Oct'97) a. 2.54 b. 3.54 c. 3.14 d. 44 6. A 50 hp three phase motor, rated 220 volts, 75% power factor has 6 poles. The slip at full load is 34. What is the frequency of the rotor current at full load? (EE Board Prob. Mar '98)

4. The speed of a 50 hz, 4 pole induction motor running with a slip of 54 will be a. 1760 rpm b. 950 rpm c. 1488 rpm d. 1425 rpm 5. A 3-phase induction motor is rated 220 volts and 1745 rpm and 784 power factor. What is the percent slip? (EE board Prob. Oct'97) a. 2.54 b. 3.54 c. 3.14 d. 44 6. A 50 hp three phase motor, rated 220 volts, 75% power factor has 6 poles. The slip at full load is 34. What is the frequency of the rotor current at full load? (EE Board Prob. Mar '98)

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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