When we were young, we were very interested in everything, especially magnets. A magnet can attract iron objects. And it also has a special property, that is, if we break a large magnet from the middle, it will become two small magnets. Each magnet has its own S pole and N pole.

I don't know how many tape recorders we destroyed to play with magnets. But how did this breaking of the magnet become two characteristics?

Magnetic force is the foundation of the earth, and the earth's magnetic field is the foundation to protect Earth's life from deadly cosmic rays. According to Maxwell's electromagnetic theory. Magnetic force is formed by the directional movement of electrons around the nucleus. When electrons move in the same direction, they will produce moving charges and then produce a magnetic field.

In fact, most substances have magnetism, but they are very weak, such as gold, silver, copper and iron. The electronic activities of these substances are almost irregular, so there is no way to form a strong magnetic field. When iron encounters a magnet, due to the influence of the external magnetic field, the electrons inside the iron will become in the same direction, so it has magnetism temporarily and can be attracted by the magnet.

If we remove the magnet, the iron object will still maintain a slight magnetic field, and when the magnetized object can maintain magnetism more efficiently, we will get a permanent magnet.

In fact, this can also explain the reason why each magnet forms when the magnet is broken into two parts. After two small magnets are formed, they will still become small magnets and will not be affected. If we keep dividing the magnets, new small magnets will be formed. Only when we divide the magnet into atomic angles will some changes occur.

Modern quantum mechanics research predicts the existence of magnetic monopole, but this is an unsustainable state, so scientists still debate whether magnetic monopole really exists.