A 240 V D.C shunt motor has an armature resistance of 0.2 Q. When the armaturecurrent is 40 A, the speed is 1000 rpm. (a) Find additional resistance R, to be connected inseries with armature to reduce the speed to 600 rpm. Assume the armature current remainsthe same. (b) If the current decreases to 20 A (with resistance R, connected) find the newspeed of the motor.

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A 240 V D.C shunt motor has an armature resistance of 0.2 2. When the armature urrent is 40 A, the speed is 1000 rpm. (a) Find additional resistance Rx to be connected in eries with armature to reduce the speed to 600 rpm. Assume the armature current remains e same. (b) If the current decreases to 20 A (with resistance R, connected) find the new need of the motor

A 240 V D.C shunt motor has an armature resistance of 0.2 2. When the armature urrent is 40 A, the speed is 1000 rpm. (a) Find additional resistance Rx to be connected in eries with armature to reduce the speed to 600 rpm. Assume the armature current remains e same. (b) If the current decreases to 20 A (with resistance R, connected) find the new need of the motor

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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