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Question
What do you understand by the term "electromagnetic induction"? Explain with the help of a diagram.
Solution
In case of relative motion between a source of magnetic field and conductor, current flows inside the conductor. This phenomenon is called electromagnetic induction. For example, when a bar magnet is moved towards a coil of wire attached to a galvanometer, a deflection in galvanometer needle is observed due to induced current as shown in the figure.
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When the magnet shown in the diagram below is moving towards the coil, the galvanometer gives a reading to the right.
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