What is Magnetization?

Experiment: Ask your mom or dad (or your teacher) for some metal paper-clips and a magnet. Can you pick up paper clips with the magnet? Can you pick up the paper clips with other paper clips?

Most paper clips are made of iron. Magnets pull on things made of iron.

Now, rub a paper clip with the magnet. Can you pick up other paper clips with it now?

The iron in the paper clip can become a magnet too: the paper clip is magnetized by rubbing it with the magnet. It doesn't magnetize all at once though: when you rub it longer, it gets more magnetized and picks up other paper clips better and better.

Magnetic tapes, like the ones you put in your tape player and your VCR, write the music by magnetizing small parts of the tape. The disk drives and floppy drives in your computer also magnetize small dots to store your files. Don't bring your magnet near your tapes or floppies! It'll erase them.

Did you listen carefully when you were rubbing the paper clip? I bet you didn't hear any crackling noise!