4. A dc shunt motor runs at 900rpm from a 400 V supply when taking an armature current of 25A.Calculate the speed at which it will run from a 230 V supply when taking an armature current of 15 A. The resistance of the armature circuit is 0.8 ohm. Assume the flux per pole at 230 V to have decreased to 75% of its value at 400V.

4. A dc shunt motor runs at 900rpm from a 400 V supply when taking an armature current of 25A.Calculate the speed at which it will run from a 230 V supply when taking an armature current of 15 A. The resistance of the armature circuit is 0.8 ohm. Assume the flux per pole at 230 V to have decreased to 75% of its value at 400V.

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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