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Name: Leo H.
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Question:
How far reaching are magnetic fields on magnets. If for example, we could show all existing field lines of a 1/2 inch x 1/2 bar magnet, how far could the weakest line travel from the pole before returning back? Is it limitless as the equations propose ? And as I move the magnet, does the field move at the same time? Does the field deform as I move the magnet? Are the field lines actual channels by which electrons travel?



Replies:
The field from a bar magnet goes to zero at infinity. (It decreases as the third power of the distance from the center of the magnet.)

As the magnet moves, the field moves with it, but there is a time lag imposed by the finite speed of light.

Field lines are not channels by which electrons travel.

--
Tim Mooney



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