Galvanometer is a sensitive device that operates on the same principle as that of an electric motor. A coil is placed between the pole pieces of a magnet in such a way that the pointer on the galvanometer dial is connected to it. When a small current (for example 1 mA) flows through the coil, the coil rotates proportional to the current. Voltmeter and Ammeter also work on the same principle. In a galvanometer, the pointer deflects on both the sides of the zero mark depending on the direction of the current. Connect the galvanometer and keep the bar magnet erect in such a way that its north or south pole is just below the copper wire. Now if the wire is kept moving from A B, the pointer of the galvanometer gets deflected. This is called Faraday’s electromagnetic induction. Now move the magnet with the wire fixed and the Galvanometer pointer still gets deflected.
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