. In a dc shunt motor, the shunt field resistance is 100 ohms and the armature resistance is 0.01 ohm. It is supplied by a 250V source. If the shunt field is disconnected and is connected to a rheostat to control the speed of the dc machine, what should be the case if it is desired to increase the speed of the motor? The resistance of the field rheostat should be decreased to be able to increase the speed of the motor The resistance of the field rheostat should be increased to be able to increase the speed of the motor The resistance of the field rheostat should not be changed to be able to increase the speed of the motor The terminals of the field rheostat should be short circuited to be able to increase the speed of the motor

. In a dc shunt motor, the shunt field resistance is 100 ohms and the armature resistance is 0.01 ohm. It is supplied by a 250V source. If the shunt field is disconnected and is connected to a rheostat to control the speed of the dc machine, what should be the case if it is desired to increase the speed of the motor? The resistance of the field rheostat should be decreased to be able to increase the speed of the motor The resistance of the field rheostat should be increased to be able to increase the speed of the motor The resistance of the field rheostat should not be changed to be able to increase the speed of the motor The terminals of the field rheostat should be short circuited to be able to increase the speed 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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