Faraday’s law of electromagnetic induction states that a current is induced in a conductor placed in a changing magnetic field. Any minute variation in the magnetic field of the coil will result in an induced emf in the coil. The ways in which the magnetic field can be varied are,
(a) The movement of a bar magnet towards and away from the coil.
(b)The movement of the coil into and out of a magnetic field.
(c) The rotation of the coil relative to the magnet will bring the variation in magnetic field.