Krampf
Experiment of the Week - Making a Magnet
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This week's experiment is the
really a prelude to next week's. I wantedto do an experiment on how to
kill a magnet, but before you can kill one, you need to know how to make
one.
To make a magnet, you will need:
* a strong,
permanent magnet
(available from Radio Shack or from craft stores.)
* several
paper clips
* steel wool
* a sheet of
paper
One of the easiest ways to make a
magnet is with another magnet. Straighten out the paper clips.
Hold a straightened paper clip by one
end and hold the magnet in the
other. Bring one end of the magnet to the paper clip at the point where
you are holding it and then slide the magnet along the paper clip to
the end. Move the magnet away from the paper clip and repeat the process
several times. Be sure that you only move the magnet along the paper
clip in one direction, away from your hand.
After doing that several times,
put away your permanent magnet and get out the paper and the steel wool.
You put away the permanent magnet because if the tiny bits of steel
wool get stuck to it, they are almost impossible to get off. If you
want to use your permanent magnet to play with the steel wool, put it in a
plastic bag first. That will keep the bits separated from the magnet.
Place the sheet of paper on a flat surface and hold the steel wool
over it. Rub two pieces of steel wool together and you will see lots of
tiny bits falling on the paper. Bring the end of your magnetized paper
clip near the steel wool and you will see it stick to the paper clip.
Your paper clip is now a magnet.
What happened to magnetize it?
Inside a piece of iron or steel are tiny groups of atoms called domains.
Each of these domains is a tiny magnet, with a north and south pole. In
unmagnetized iron, they domains are arranged randomly with their
north and south poles pointing in different directions. The
magnetic fields cancel each other out, and so the piece is not a magnet. When
you move the magnet along the steel of the paper clip, the magnet pulls
on each domain and shifts the north and south pole, so that most of
them wind up pointing in the same direction, and the paper clip is
then a magnet. The more domains you get lined up, the stronger the
magnet will be.
While you are playing with your
magnet, check to see which parts of your magnet have the strongest
magnetic field. You can also notice how much of the steel wool the magnet
will pick up when it is straight and then bend it into a horseshoe
shape, where the two ends are near each other and try again. Does a
horseshoe magnet pick up more than a straight, bar magnet?
Be sure to keep your magnets.
Next week, we will try to destroy the magnetism in them.