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Question
State Faraday’s laws of electromagnetic induction.
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Solution 1
First law: Whenever there is a change of magnetic flux in a closed circuit, an induced emf is produced in the circuit. This law is a qualitative law as it only indicates the characteristics of induced emf.
Second law: The magnitude of the induced emf produced in the circuit is directly proportional to the rate of change of the magnetic flux linked with the circuit. This law is known as the quantitative law, as it gives the magnitude of the induced emf.
Solution 2
Faraday’s First Law: Whenever the magnetic flux linked with a circuit changes, an emf is induced in the circuit.
Faraday’s Second Law: The magnitude of the induced emf is equal to the rate of change of magnetic flux.
e = `-(d phi)/dt`
For a coil of N turns:
e = `-N (d phi)/dt`
Negative sign indicates Lenz’s law (direction opposes cause).
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