The nature of the magnet
The magnet has two polarities, a magnetic north pole N and a magnetic south pole S. After being cut off, it is still a two-pole N-level and S pole. No single pole can exist. At the same time, the magnet is directional. If you hang a magnet, you will find that its south pole points to the left and right of the geographic south pole, and the north pole points to the left and right of the north pole.