Prob. 12. A D.C. series motor runs at 500 r.p.m. drawing 40 A from 600supply. Determine the value of the external resistance to be added in serieswith the armature for the motor to run at 450 r.p.m. The load torque vwriesas the square of the speed. Assume linear magnetisation and take armatureresistance as 0.3 ohm and series field resistance is 0.2 ohm.

Answered: Image /qna-images/answer/c1e062f8-eca1-4a70-9672-f6fc4ce4b1bd.jpg

Prob. 12. A D.C. series motor runs at 500 r.p.m. drawing 40 A from 600 V supply. Determine the value of the external resistance to be added in serivr with the armature for the moter to run at 450 r.p.m. The load torque varies as the square of the speed. Assume linear magnetisation and take armature resistance as 0.3 ohm and series field resistance is 0.2 ohm.

Prob. 12. A D.C. series motor runs at 500 r.p.m. drawing 40 A from 600 V supply. Determine the value of the external resistance to be added in serivr with the armature for the moter to run at 450 r.p.m. The load torque varies as the square of the speed. Assume linear magnetisation and take armature resistance as 0.3 ohm and series field resistance is 0.2 ohm.

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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