What is the principle of compass?

The principle of the compass is to use the magnetism of the north and south poles to guide the way.

Compass is one of the four great inventions in China. The principle of a compass is to use a magnetic needle mounted on a shaft. Under the action of natural geomagnetic field, the magnetic needle can rotate freely and keep in the tangential direction of magnetic meridian. The south pole of the magnetic needle points to the geographical south pole (magnetic north pole), and the direction can be distinguished by using this property.

Compass is the result of China ancient working people's understanding of magnet magnetism in long-term practice. As one of four great inventions of ancient china, its invention has played an inestimable role in the development of human science, technology and civilization. In ancient China, the compass was first used for rituals, etiquette, military affairs and divination, and to determine the orientation when looking at geomantic omen.

The compass was introduced to the west.

China's magnetic needle and compass spread to the west by land and water successively, which had a great influence on the progress of human civilization. Historians believe that the water compass with a magnetic needle floating in the water comes down in one continuous line with the compass, which was invented by China. 1985 The dry compass held by the figurine "Zhang" unearthed from Zhu Jinan's tomb in Linchuan, Jiangxi Province in the Southern Song Dynasty proves that the invention right of the dry compass also belongs to China.