What are magnets?
How do they act with other magnets and with other objects?
What You Need
What You Do
What to do for Experiment #1 - How do magnets act with another magnet?
Experiment #2- Which objects will be attracted to or cling to a magnet?
What Is Happening
Magnets are typically made of a metal we call iron. Many things we see and use that are magnetized are made out of steel or have iron in them. One of the metals in steel is iron. Iron, like everything else, is made of little building blocks we cannot see that we call atoms.
In things that are not magnetized, the little atoms are all mixed up and pointing in many different directions. In a magnet, the atoms get lined up in straight rows with their north ends pointing towards the North Pole and their south ends pointing towards the South Pole. [This is over-simplified for younger children. Atoms function like tiny electromagnets; in a magnet, all the atoms have their electrons spinning about their nuclei in the same direction.] Magnets attract and stick to other objects that are magnetized, or have their atoms all lined up in rows facing North and South Poles.
Magnets have magnetism or the power to pull other objects to them. They also can be used to push away other magnets. There is a story about how we came up with the word "magnet." Supposedly there was a shepherd tending his sheep long ago on an island called Magnesia. This island was part of the Greek Islands. The shepherd put a piece of iron on the bottom of his walking stick so it wouldn't get worn out so fast. He saw that some stones seemed to stick to the bottom of his walking stick. These stones were natural magnets called "lodestones." The shepherd had to pick these little black stones off of his stick because they seemed to be stuck!
Magnets are lots of fun to play with. Have you ever played with a toy Woolly Willie, which is a completely bald head and face that you can add hair to by using a magnetic "pencil" or stylus? The face is covered by a clear plastic enclosure that holds iron shavings, which are attracted by the stylus.
We use magnets for many different purposes. Try to think of some of the ways in which we use magnets. What about magnets you might have at home on your fridge? A refrigerator is made out of steel. So if you have a magnet on the fridge, it is pulling on the little atoms of steel in the door.
You can make some iron or steel objects act like a magnet for a little while by lining up their atoms. Take a nail and rub it over and over in the same direction with the end or pole of a bar magnet. Lift the magnet up each time your stroke gets to the end of the nail, and start again at the same place with each new stroke. Do this about 40 times. For a while, the nail will be magnetized because its atoms are all lined up. Try using it as a magnet: see if it will attract a paper clip or thumbtack.
Want to Do More?
If you want to experiment further, find out by experimenting that substances that can be magnetized are not transparent to magnetism. If something is transparent to magnetism, that means the magnetic waves can pass right through it. For example, magnetism passes through glass, plastic, cloth, and the human body. Get an empty "tin" can (which is really an iron-containing steel), remove both ends, and flatten it. Then put it in between a magnet and some nails or other magnetizable objects. You will no longer be able to pick up the nails with the magnet. Now, think about the consequences: a magnetic compass would be no use at all to submariners, because the earth's magnetic waves cannot pass through the sub's steel walls to get to it.