How Does a Compass Know Which Way is North?

A compass is like a tiny magnet that wants to be friends with the biggest magnet in the world, the Earth. The needle on a compass points north because it follows the Earth's magnetic field, just like how a magnet attracts paper clips.

How It Works A compass has a [magnetic needle](/search?q=magnetic%20needle) that can spin freely. When you hold it up, the needle moves until it lines up with the Earth’s north and south [poles](/search?q=poles), that's why it always points north! It doesn’t know where north is, but it follows the invisible lines of magnetism around the world.

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A compass needle is like a tiny magnet that always follows the Earth's invisible lines of magnetism.
If you put a compass on your table and spin it around, the needle will still point north, it just takes time to settle.
A compass works even underwater or when it’s moving in a boat, it doesn’t need anything else to work.

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Categories: Science · magnetism,navigation,earth science