Magnets and magnetic fields

Magnets have a north and a south pole. Around them is a magnetic field, which we draw with field lines going from north to south. Only some materials are magnetic.

Key facts

  • Like poles repel; unlike poles attract.
  • Field lines go from N to S; closer lines mean a stronger field.
  • Magnetic materials: iron, steel, nickel and cobalt.
  • A compass needle lines up with the field; Earth acts like a giant bar magnet.

Worked examples

Example 1

A north pole is brought near the north pole of another magnet. What happens?

  1. Like poles repel, so they push apart.

Answer: They repel