(c) A dc series motor, connected to a 440 V supply, runs at 500 rpm when taking a current of 40 A. Calculate the value of resistance which, when inserted in series with the motor, will reduce the speed to 300 rpm, the gross torque being then half its previous value. The resistance of the motor is 0.2 ohm. Assume flux to be proportional to field current.

(c) A dc series motor, connected to a 440 V supply, runs at 500 rpm when taking a current of 40 A. Calculate the value of resistance which, when inserted in series with the motor, will reduce the speed to 300 rpm, the gross torque being then half its previous value. The resistance of the motor is 0.2 ohm. Assume flux to be proportional to field current.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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