Which instrument do you use to determine your position relative to the North Pole?
A compass is a device that indicates direction. It is one of the most important instruments for navigation.
Magnetic compasses are the most well known type of compass. They have become so popular that the term “compass” almost always refers a magnetic compass. While the design and construction of this type of compass has changed significantly over the centuries, the concept of how it works has remained the same. Magnetic compasses consist of a magnetized needle that is allowed to rotate so it lines up with Earth's magnetic field. The ends point to what are known as magnetic north and magnetic south.
Scientists and historians don’t know when the principles behind magnetic compasses were discovered. Ancient Greeks understood magnetism. As early as 2,000 years ago, Chinese scientists may have known that rubbing an iron bar (such as a needle) with a naturally occurring magnet, called a lodestone, would temporarily magnetize the needle so that it would point north and south.
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