Magnetic compass projection light tube

The working principle of the magnetic compass is based on the earth's magnetic field. The earth has a huge magnetic field, magnetic field lines from the south pole of the earth through the earth to the north pole. The magnetic compass uses this magnetic field to indicate direction.
There is a magnetic needle inside the magnetic compass. In the case of free rotation, the magnetic needle will automatically align with the earth's magnetic field. The north pole of the magnetic needle always points to the south pole of the magnetic field, so that the indicator is the north and south pole. Magnetic needles are made of magnetic materials, usually steel or cobalt. These materials have a special property, called magnetism, which can have a specified direction under the influence of an external magnetic field.
In a static environment, a magnetic needle pointing in the direction of the earth's magnetic field can determine the north. But when the magnetic Luo
When moving with the movement of people or ships, the magnetic needle will be affected by other interference factors (such as other magnetic substances in the cabin, etc.), resulting in a deviation in the direction of pointing. To eliminate this interference, we need
Mark some stable directions on the magnetic compass, such as the north-south direction and the east-west direction, and then according to these marks.
Remember to adjust the point of the magnetic needle to ensure the accuracy of the indicator.