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The motion of copper plate is damped whe...

The motion of copper plate is damped when it is allowed to oscillate between the two poles of a magnet what is the cause of this damping ?

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i. As the plate oscillate, the changing magnetic flux through the plate produces a strong eddy current in the direction, which opposes the cause.
ii. Also copper being diamagnetic substance, it gets magnetised in the oppsite direction, so the motion of copper plate is stopped.
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