The field winding of a.d.c. machine takes a steady current of 10A when connected to a d.c. source of 230 volts.On, switching the voltage to the field, it is observed that it takes O.3 second to reach 5 A. (i) Find the value of inductance of the field winding. (ii) Find also the time for the current to fall to 30% of the final steady value if the field terminals are short - circuited.

The field winding of a.d.c. machine takes a steady current of 10A when connected to a d.c. source of 230 volts.On, switching the voltage to the field, it is observed that it takes O.3 second to reach 5 A. (i) Find the value of inductance of the field winding. (ii) Find also the time for the current to fall to 30% of the final steady value if the field terminals are short - circuited.

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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