Principle and Working:
An induced e.m.f. (or induced current) is produced across a conductor when it is exposed to a change in a magnetic field. The mathematical law that relates the changing magnetic field to the induced current (or the induced voltage) is called Faraday's Law.
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Lenz’s law describes the magnetic flux through the circuit and gives the direction of the induced e.m.f. This gives rise to induced current which opposes the change in magnetic flux .
In the present setup, a permanent magnet falls with different velocities through a coil. The change in the magnetic flux generates an induced voltage impulse. The induced voltage impulse is recorded with voltage probe through Data Logger. Depending on the polarity of the permanent magnet the induced voltage impulse is negative or positive.