How to make a compass

Tool materials: paper clips, waste bottle caps, pliers, powerful magnets (which can be removed from waste speakers), glue, scissors and markers.

Production steps:

1. Straighten an ordinary stationery paper clip with pliers and cut it to a proper length.

2. Put the straightened paper clip on one pole of the magnet and rub it in the same direction for more than 20 times. Be careful not to let the needle prick your hand. Check whether the magnetic needle is ready.

The easiest way is to put it next to the compass of another finished product and check whether the compass pointer is deflected because of the proximity of the magnetic needle.

3. Black one end of the magnetized pointer with a marker, punch two opposite holes on the side of the beverage bottle cap, and insert the magnetized pointer into the hole cover.

4. Stick the pointer on the bottle cap with glue, and a simple version of the floating compass will be made.

When using this DIY compass, as long as it is placed on the still water and attracted by the earth's magnetic pole, the compass will slowly rotate on the water until it points out the correct north-south direction for you.

Compass, called Sina in ancient times, is mainly composed of magnetic needles installed on the 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.

It is often used in navigation, geodesy, tourism and military affairs. The invention of the compass with physical direction indication has three parts, namely Sina, compass and magnetic needle, all of which belong to the invention of China. According to ancient mine records, it first appeared in the Cishan area during the Warring States Period.

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.