Final answer:
To induce an electric current in a coil with a bar magnet, you must move the magnet in relation to the coil, which can be done by moving it towards, through, or away from the coil. This creates a changing magnetic flux that induces the current, as per Faraday's Law of Electromagnetic Induction and the Right Hand Rule.
Step-by-step explanation:
To cause an electric current to flow in a coil of wire using a bar magnet, you would need to move the magnet relative to the coil. This movement should either be towards the coil, away from the coil, or through the coil. Michael Faraday's experiments demonstrated that an electric current is induced in the coil only when there is relative motion between the magnet and the coil. If you move the magnet in one direction and then reverse it, the current induced will also reverse direction. Additionally, reversing the poles of the magnet will cause the current to flow in the opposite direction. This phenomenon is a result of the change in magnetic flux through the coil when the magnet moves, which is described by Faraday's Law of Electromagnetic Induction. As per the Right Hand Rule, if a bar magnet's south pole is moved towards a conducting loop, the current induced will be in such a direction that it creates a magnetic field opposing the change in flux; thus, a south pole is created on the face of the loop nearest the approaching magnet. Moreover, if you were to use a voltmeter in an experiment as described above, you would be able to observe the polarity of the induced voltage as the magnet moves in relation to the coil.
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