On what principle was the compass invented?

Compass is invented according to the principle of magnet;

The earth is a big magnet, and its poles are close to the geographical south pole and the geographical north pole respectively. When the magnets on the earth's surface can rotate freely, they will indicate the north and south because of the nature that like magnets repel and opposite magnets attract.

The compass was called Sina in ancient times, and its main component was a magnetic needle mounted on the shaft. Under the action of natural geomagnetic field, the magnetic needle can rotate freely and keep in the tangent direction of magnetic meridian, and the north pole of the magnetic needle points to the geographical north pole, so the direction can be distinguished by 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.

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Influence of compass:

The application of compass in navigation has greatly promoted the great geographical discovery and maritime trade. The invention of the compass originated from the study of how the ancient people in China oriented, and also showed that the ancient people attached importance to how to orient. Therefore, the compass is known as one of four great inventions of ancient china.

In ancient China, compasses were used for military and maritime activities, and also for geomantic omen theory. Later, it was introduced to Europe, which played an irreplaceable role in European navigation and geographical discovery. In the invention of navigation technology, compass is also the most important single invention.

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