Which statement of Lenz's law is correct?
Answer and explanation
Correct answer: D. The induced current flows in a direction that opposes the change causing it
- Step 1: Lenz's law follows from conservation of energy: if the induced effect assisted the change, energy would be created from nothing. Answer: The induced current flows in a direction that opposes the change causing it. Why not the others: a reinforcing effect would create unlimited energy; emf depends on the rate of change of flux, not on the flux itself; a closed circuit carries an induced current.
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