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प्रश्न
State Faraday’s laws of electromagnetic induction.
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उत्तर १
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.
उत्तर २
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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संबंधित प्रश्न
State Lenz’s Law.
- How would you demonstrate that a momentary current can be obtained by the suitable use of a magnet, a coil of wire and a galvanometer?
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- Describe briefly one way producing an induced e.m.f?
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- What factor determines the direction of induced e.m.f. in part (a) above?
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If magnetic flux changes by \[\Delta\Phi_B\] in a time interval \[\Delta t\], which expression gives the induced emf \[e\]?
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What is the induced emf if both a magnet and a coil remain stationary?
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Which condition is a limitation of Faraday’s First Law or Neumann’s law?
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What interaction opposes a north pole moving away from the near face of a coil?
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