Magnets and Spheres
Name: Frank H.
Is it possible for a magnet to exist in the shape of a ball?
If so, are the poles identifiable and do the poles repeat?
Sure. A magnet can be cut into any shape you like. For example,
you could take a bar magnet and machine it into a number of individual,
spherically-shaped magnets. The hard magnetization direction, or "poles"
that were present in the original bar magnet would still be there in the
little ball magnets.
I'm not sure what you maen by "do the poles repeat ".
Yes, one can make a magnet in the shape of a ball. To make a magnet in
one first makes a "mold" of the desired part using a ferromagnetic powder
the simplest form, machine it from a block of iron. One then magnetize it
the pattern one wants by applying a magnetic field. In the case of ball, a
ferromagnetic ball is made and then a magnetic field is allied to it to
it in the direction of the poles-to-be. This way you can place the poles
you want on the ball.
Ali Khounsary, Ph.D.
Advanced Photon Source
Argonne National Laboratory
A common example of a magnet in the shape of a ball is the Earth. Where the
poles of a magnet are does not depend on the shape of a magnet, but on how
the individual atoms line up. Each atom is a magnet. If they all line up
in the same direction, you have a strong magnet. In most materials, the
atoms don't stay lined up. In a few materials, such as iron, they do stay
lined up. Place an iron ball in a strong magnetic field. Leave it there
for a little while. When you remove the ball, north and south poles will be
opposite each other. Exactly where will depend on how it was originally
Yes, a prime example would be the earth, with one north and one south pole.
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Update: June 2012