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Question
- How would you demonstrate that a momentary current can be obtained by the suitable use of a magnet, a coil of wire and a galvanometer?
- What is the source of energy associated with the current obtained in part (a)?
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Solution
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Move the N-pole of the magnet along the coil, until it reaches the B-end of the coil that is linked to the center zero galvanometer. To indicate that current is flowing in the coil, the pointer deflects to the right. An increase in the rate of current production occurs when the N-pole is moved closer to B, meaning that the coil and magnet are moving relative to one another. No such current is generated and the pointer stays at zero when both are at rest.

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The source of energy associated with the current obtained in part (a) is mechanical energy.
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