Nature magnet

A magnet can attract or repel each other mutually substance, if an object inside a small molecule can be arranged in the same direction, it will become a magnet. Component is iron, cobalt, nickel and other special atomic structure, atomic magnetic filtration itself, the general confusion molecular arrangement of these minerals. Magnetic domain magnetic influence each other to not show, but external forces (such as magnetic field) molecules arranged in a direction guided by a consistent trend, it showing magnetic, also known as magnet. Iron, cobalt, nickel, is the most common magnetic substance, basically divided permanent magnets and magnet soft iron, the permanent magnet is coupled magnetic rods, the spin of the electron angular momentum of a magnetic substance arranged in a fixed direction, it is soft plus current (also a plus magnetic method) or the like to remove the current soft magnetic iron will slowly lose. Magnet is not human invention, a natural magnetite, first discovered and use magnets should be Chinese. Therefore, the "Compass" is one of the four great inventions of the Chinese people