A compass needle points north because the north pole of the magnet inside it is attracted to the south pole of Earth's built-in magnet.
Step-by-step explanation:
- A compass points north because all magnets have two poles , a north pole and a south pole, and the north pole of one magnet is attracted to the south pole of another magnet. (You may have seen this demonstrated by a pair of simple bar magnets or refrigerator magnets pushed end to end.)
- The Earth is a magnet that can interact with other magnets in this way, so the north end of a compass magnet is drawn to align with the Earth's magnetic field. Because the Earth's magnetic North Pole attracts the "north" ends of other magnets, it is technically the "South Pole" of our planet's magnetic field.
- While a compass is a great tool for navigation, it doesn't always point exactly north. This is because the Earth's magnetic North Pole is not the same as "true north," or the Earth's geographic North Pole . The magnetic North Pole lies about 1,000 miles south of true north, in Canada.
- This difference between true north and the north heading on a compass is an angle called declination. Declination varies from place to place because the Earth's magnetic field is not uniform it dips and undulates.
- If you followed the compass to the north, you would not actually end up at the North Pole because the magnetic poles of the Earth move slowly over time