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Does the electromagnetically induced emf in a coil depend on the resistance of the coil? Why?

Wrichik Basu
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Divya Sathya
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    Although Faraday's law has no mention of resistance there may be cases when the induced emf may be dependent on the resistance of a circuit in which the emf is induced. If an induced emf produces an induced current that current will try and oppose the change producing the induced emf (Lenz). That opposition may make the circuit move slower, reduce the rate of change of flux linkage with the circuit and hence reducing the induced emf. – Farcher Sep 03 '17 at 05:44
  • That's a great observation @Farcher. Thanks for that. – Wrichik Basu Sep 03 '17 at 06:01

1 Answers1

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As per Faraday's Law of Electromagnetic Induction, $$\epsilon =- N \dfrac {d\Phi}{dt} $$ where $\epsilon $ is the induced EMF, $\dfrac {d\Phi}{dt} $ is the change in flux per unit time, and $N$ is the number of turns in the coil.

From the formula, it is evident that the induced EMF does not depend on the resistance of the coil or wire.

However, if the induced EMF produces a current, then that produced current will depend on the resistance of the coil or wire. The produced current will result in a tendency to oppose the induced EMF, thereby in a tendency to oppose the rate of change of the flux (Lenz's Law), as a result of which the induced EMF will be decreased.

Thus, if a current is produced on the coil, then the resistance affects the induced EMF.

Wrichik Basu
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