Same chapter3 marksDifficulty: Medium
A coil of 200 turns experiences a change of flux of 0.02 Wb in 0.1 s. Find the induced emf.
Electromagnetic Induction and Alternating Currents
3 marksDifficulty: Medium
State Faraday's laws of electromagnetic induction and Lenz's law.
Original Khojo Papers practice question — not from a past board paper.
Answer
Faraday's first law states that an emf is induced whenever the magnetic flux linked with a circuit changes, and the second that the magnitude of the emf equals the rate of change of that flux. Lenz's law states that the induced current always opposes the change producing it, and it is the reason for the negative sign in the formula.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Lenz's law is a consequence of the conservation of energy.
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