We often say that a magnet, also known as a magnet, is a stone that can adsorb iron, as the name suggests. At first, people discovered a natural ore called magnetite (iron trioxide) that could adsorb iron products. After extensive attempts, they found that these stones could not only adsorb metals such as gold, silver, copper, but also objects such as bricks and tiles. They could only attract iron products.

With the development of technology, the application of magnetism has become more widespread, including magnetic levitation, magnetic resonance, and even the previously proposed "electromagnetic cannon". Some drivers also place a magnet outside the exhaust pipe to prevent backflow. But do you know why magnets have magnetism? Do you really understand magnets? I once saw a question like this: Why don't there be magnetic gold, magnetic silver, or magnetic copper when there is a magnet?

Later, with the development of magnetism, we referred to substances with the properties of attracting ferromagnetic substances such as iron, nickel, cobalt, and other metals as magnets, which are substances with their own magnetic moments. (Because magnetic moment is the source of all magnetic phenomena) So a magnet is not iron, it is just a general term for a class of substances, let alone magnetic gold or silver.

The magnetism of matter

In fact, everything in the world has magnetism, whether it's the desks and benches around us, the molecules and atoms that make up matter, or even the planets. It's just that some substances show magnetism to the outside, while others do not show magnetism to the outside.

When it comes to the origin of magnetism, we should start with the origin of matter. It is known that matter is composed of molecular atoms, which contain atomic nuclei and a large number of electrons inside the atoms. These electrons within the atom undergo spin motion and orbital motion around the nucleus.