Question Detail

PHY 102 Electromagnetic Induction Objective Question
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Question

What is back emf in an electric motor?
Options
A The emf that increases the applied voltage
B The emf generated by the rotating armature that opposes the applied voltage
Correct Answer
C The emf from the power supply
D The emf from the field windings only
Correct Answer

Option B is the correct answer.

Detailed Explanation

When the armature rotates in a magnetic field, it generates an induced emf (back emf) that opposes the applied voltage, reducing the net current through the motor.

Hint

Opposes the applied voltage.

Question Info

Course: PHY 102
Topic: Electromagnetic Induction
Type: Objective
Difficulty: Not specified
Question 21 of 1819
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