The rotor of an electric motor has an angular velocity of 3570 rpm when the load and power are cut off. The 65-kg rotor, which has a centroidal radius of gyration of 175mm, until it reaches the maximum speed of 5250 rpm. Knowing that the kinetic friction results in a couple of magnitude 4.5 N.m exerted on the rotor, determine the number of revolutions that the rotor executes, before achieving its maximum speed and the time it took.

The rotor of an electric motor has an angular velocity of 3570 rpm when the load and power are cut off. The 65-kg rotor, which has a centroidal radius of gyration of 175mm, until it reaches the maximum speed of 5250 rpm. Knowing that the kinetic friction results in a couple of magnitude 4.5 N.m exerted on the rotor, determine the number of revolutions that the rotor executes, before achieving its maximum speed and the time it took.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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