Do you know about magnets? A magnet is a very magical thing that can hold onto some iron objects, such as nails, keys, scissors, and so on. Are you curious why magnets have such abilities? Where does the power of a magnet come from? Will it disappear?

In fact, the power of a magnet is generated by some very small things inside it. These things are called atoms, and you can imagine them as small balls, each with smaller balls spinning around. These smaller balls are called electrons, and they are like some miniature batteries that can generate electricity and magnetic fields. Each electron has a front and a back, which we call a magnetic pole.

The number and arrangement of electrons in different atoms are different, so the magnetic field they generate is also different. In some atoms, the magnetic field of the electrons just cancels out, so there is no magnetism. In some atoms, the magnetic field of electrons is not completely cancelled out, so there is a bit of magnetism. In some atoms, the magnetic field of electrons is very strong, so they have strong magnetism. For example, elements such as iron, cobalt, and nickel are like this.

When these highly magnetic atoms gather together to form matter, their magnetic fields also interact with each other. If they are randomly arranged, their magnetic fields will also cancel out each other, and the material will not have obvious magnetism. If they are arranged in a certain direction, their magnetic fields will strengthen each other, and the material will have obvious magnetism. We call these atoms arranged in the direction magnetic domains.

In general, there are many magnetic domains in different directions in a substance, and they are in equilibrium with each other, so the substance has no obvious magnetism. But if a substance is affected by external magnetic fields, temperature, pressure, and other factors, some of their magnetic domains will change direction, causing the entire substance to present a unified direction, and the substance becomes a large magnet. We call this process magnetization.