According to Lenz's law, what is the direction of an induced current in a closed loop?
Answer and explanation
Correct answer: A. Opposes the change in magnetic flux that produces it
- Step 1: Lenz's law is an expression of the law of conservation of energy.
- Step 2: It states that an induced electromotive force always gives rise to a current whose magnetic field opposes the original change in magnetic flux producing it.
Answer
Opposes the change in magnetic flux that produces it.
Why not the others: 'Always in the direction of the external magnetic field' would cause runaway magnetic amplification violating conservation of energy; 'Always perpendicular to the plane of the loop' is the direction of the magnetic moment, not the loop current; 'In the direction that maximizes the net current' is physically incorrect.
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