Answered: / choose the correct answer The back…

/ choose the correct answer The back emf in a dc motor is ___________________?. 1-opposes the applied voltage 2- aids the applied voltage 3- opposes the field current 4- aids the armature current

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter10: Contactors, Relays, And Overloads

Section: Chapter Questions

Problem 32RQ

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Concept explainers

DC Series Motors

A DC motor is a type of electric motor which converts electric energy into mechanical energy. The forces that are produced by the magnetic field are what those common types of motors rely upon. Either electro-mechanical or electronic, all types of DC motors have some internal mechanism to change the current direction in part of the DC motors. As the DC motors could be powered from existing DC lighting power distribution systems, these motors were the first form of motors widely used. By changing the strength of the current in its field winding or by using a variable supply voltage, the speed of the DC motors can be controlled over a wide range.

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Q4/

choose the correct answer

The back emf in a dc motor is ___________________?.

1-opposes the applied voltage

2- aids the applied voltage

3- opposes the field current

4- aids the armature current

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