If the motor is overloaded then the magnitude of back e.m.f:
Correct answer: B. Decrease
- A. Increase
- B. Decrease
- C. Becomes Zero
- D. Remains constant
Explanation
When a motor is overloaded, its speed decreases due to the increased load. As a result, the magnitude of the back electromotive force (e.m.f.) also decreases. This is because back e.m.f is proportional to the motor's speed. As V = Eb + Ia Ra
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About Faraday's Law
Faraday's law states that an induced electromotive force equals the rate of change of magnetic flux linkage through a circuit. Questions cover changing field, area, angle or motion, the negative sign associated with Lenz's law, and the distinction between induced emf and the current that may flow in a closed circuit.
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