A 240 V separately excited de motor has a nominal armature current of 50 A. The armature resistance is 0.20 N. If the machine is operating at rated voltage, and the friction and windage losses are 200 W, (a) what is the back e.m.f (E)? (b) find the power supplied to the armature. (c) what is the mechanical power developed by the motor? (d) what is mechanical power at the shaft of the motor?

A 240 V separately excited de motor has a nominal armature current of 50 A. The armature resistance is 0.20 N. If the machine is operating at rated voltage, and the friction and windage losses are 200 W, (a) what is the back e.m.f (E)? (b) find the power supplied to the armature. (c) what is the mechanical power developed by the motor? (d) what is mechanical power at the shaft of the motor?

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter5: Resistors

Section: Chapter Questions

Problem 1PA

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