An electromotive force (e.m.f.) is induced in a circuit, when the magnetic flux through the circuit is
Correct answer: C. varying
- A. low
- B. high
- C. varying
- D. constant
Explanation
The correct answer is Option C: varying. According to Faraday's law of electromagnetic induction, an electromotive force is induced in a circuit when the magnetic flux through the circuit is changing or varying. This change in magnetic flux creates a voltage in the circuit. Options A, B, and D are incorrect because a low, high, or constant magnetic flux does not induce an electromotive force unless it is varying.
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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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