Magneettikompassit

Magneettikompassit are navigational instruments that utilize a magnetized needle, free to rotate on a pivot, to align itself with the Earth's magnetic field. This alignment allows the needle to indicate the direction of magnetic north, which is a close approximation of true geographic north. The Earth's magnetic field is generated by the motion of molten iron in its outer core, creating a magnetic dipole that extends into space.

The simplest magnetic compass consists of a needle housed within a casing, often filled with a liquid to dampen the needle's oscillations and provide a more stable reading. This liquid can be oil, alcohol, or a special transparent fluid. The casing typically includes a compass rose, a circular dial marked with cardinal directions (North, South, East, West) and intermediate points, enabling users to determine bearings.

Magnetic compasses are widely used for terrestrial navigation, particularly in hiking, orienteering, and maritime activities. They are reliable as they do not require external power sources or satellite signals, making them a valuable backup in situations where electronic navigation fails. However, magnetic compasses can be affected by local magnetic anomalies, such as those caused by iron deposits or electronic devices, which can lead to inaccurate readings. Understanding these limitations and knowing how to compensate for declination (the difference between magnetic north and true north) is crucial for accurate navigation.