If an electric motor is overloaded, then the magnitude of back electromotive force (e.m.f.) will
Correct answer: B. decrease
- A. increase
- B. decrease
- C. become zero
- D. remain the same
Explanation
When an electric motor is overloaded, it slows down due to the increased load. This decrease in speed results in a decrease in the back electromotive force (e.m.f.). Option B is correct because the back e.m.f. will indeed decrease in this scenario. Options A, C, and D are incorrect as they do not consider the relationship between motor speed and back e.m.f.
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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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