Why do compasses point North and South?

Why do compasses point North and South?

• A. Because of the Earth's magnetic field
• B. Because of the Earth's rotation
• C. Because the Moon's gravity
• D. Because heat magnetizes the needle

Answer: (A)

A compass points north and south because the Earth has a magnetic field that acts on a small magnetized needle. The needle is a tiny magnet, so it tends to align with the surrounding magnetic field. The end of the needle that we call its north-seeking pole is attracted to the magnetic south pole of Earth, which lies near the geographic North Pole. So the needle swings until it points toward that direction, giving us north and south on the map. Think of Earth as a giant bar magnet with a flowing iron core creating a global magnetic field. Local features—like nearby magnets or metal debris—can tug the needle a bit, but the overall direction comes from the planet’s magnetic field, not from rotation, Moon gravity, or heating.

A compass points north and south because the Earth has a magnetic field that acts on a small magnetized needle. The needle is a tiny magnet, so it tends to align with the surrounding magnetic field. The end of the needle that we call its north-seeking pole is attracted to the magnetic south pole of Earth, which lies near the geographic North Pole. So the needle swings until it points toward that direction, giving us north and south on the map.

Think of Earth as a giant bar magnet with a flowing iron core creating a global magnetic field. Local features—like nearby magnets or metal debris—can tug the needle a bit, but the overall direction comes from the planet’s magnetic field, not from rotation, Moon gravity, or heating.