Maybe you already know lots of facts about magnets.
That every magnet has a north pole (N) and a south pole (S). That unlike poles are attracted to each other, and like poles repel each other. That the strongest parts of a magnet are near the poles. That if you break a magnet into pieces, north and south poles form on each part. That magnets attract coins, thumbtacks, and other objects. These kinds of objects are made of ferromagnetic materials like iron. (The word ferro comes from Latin and means “iron.”) It’s great to know all these facts. But what actually causes magnetism? To understand that, you have to be ready to think small.
