Magnets and Magnetic Poles

Core Idea

A magnet is an object that can attract certain metals like iron, nickel, and cobalt. Every magnet has two ends called poles — a north pole and a south pole. The magnetic force is strongest at the poles. If you bring two magnets together, opposite poles attract (north pulls toward south) and same poles repel (north pushes away from north). This is how compasses work — a magnetized needle is attracted toward Earth's magnetic north.

How It's Best Learned

Give students bar magnets to explore. Let them discover which objects in the classroom are attracted to the magnet. Show how two magnets interact by bringing different poles together. Float a magnet on water or hang one from a string to make a simple compass.

Common Misconceptions

• Magnets attract all metals. (Magnets only attract certain metals like iron, nickel, and cobalt. They do not attract aluminum, copper, or gold.)
• A magnet's force is the same all over. (The force is strongest at the two poles and weaker in the middle.)
• If you break a magnet in half, you get a separate north piece and a separate south piece. (Each piece becomes a complete magnet with its own north and south poles.)
• Magnets work because of electricity. (Permanent magnets work because of the arrangement of atoms inside them, not because of an electric current.)

Explainer

Pick up a magnet and hold it near a paper clip, and you will feel an invisible tug. The paper clip jumps right onto the magnet as if pulled by an unseen hand. That pull is a magnetic force, and it is one of the fundamental forces of nature. Magnets can attract objects made of certain metals — mostly iron, nickel, and cobalt — without needing to touch them.

Every magnet has two ends called poles: a north pole and a south pole. The magnetic force is strongest at these two spots. If you dip a bar magnet into a pile of iron filings, you will see the filings cluster thickly at both ends and barely stick to the middle. The poles are where the action happens.

The really fun part comes when you bring two magnets together. If you point the north pole of one magnet toward the south pole of another, they snap together — opposite poles attract. But flip one magnet around so that two north poles face each other, and you feel them push apart — like poles repel. You can actually feel the push in your hands even though the magnets never touch. This invisible push and pull is the magnetic force at work.

Earth itself is a giant magnet. It has a magnetic north pole and a magnetic south pole, which is why a compass needle, itself a small magnet, always points north. Sailors and explorers used this property for hundreds of years to navigate the oceans. Magnets are also inside your headphones, your refrigerator door, and electric motors. From tiny fridge magnets to massive industrial cranes that lift cars, the simple rule — opposites attract and likes repel — explains it all.