If the speed of a D.C. shunt motor is increased, the back e.m.f. of the motor will_________?
Correct answer: A. increase
- A. increase
- B. decrease
- C. remain same
- D. become zero
Explanation
For a shunt motor, field flux is nearly constant and back emf is approximately proportional to speed, since Eb is proportional to flux times speed. Therefore, increasing speed increases the back emf.
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