Simple Phenomena of Magnetism

2026 What You Need to Know (Syllabus Objectives)

By the end of this topic, you should be able to:

Core:

  1. Describe the forces between magnetic poles and between magnets and magnetic materials, including the use of the terms north pole (N pole), south pole (S pole), attraction and repulsion, magnetised and unmagnetised.
  2. Describe induced magnetism.
  3. State the differences between the properties of temporary magnets (made of soft iron) and the properties of permanent magnets (made of steel).
  4. State the difference between magnetic and non-magnetic materials.
  5. Describe a magnetic field as a region in which a magnetic pole experiences a force.
  6. Draw the pattern and direction of magnetic field lines around a bar magnet.
  7. State that the direction of a magnetic field at a point is the direction of the force on the N pole of a magnet at that point.
  8. Describe the plotting of magnetic field lines with a compass or iron filings and the use of a compass to determine the direction of the magnetic field.
  9. Describe the uses of permanent magnets and electromagnets.

Supplement: 10. Explain that magnetic forces are due to interactions between magnetic fields. 11. Know that the relative strength of a magnetic field is represented by the spacing of the magnetic field lines.

1. Magnetic Poles and Forces

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What is a Magnet?

A magnet is an object that can attract certain materials (like iron) and can also attract or repel other magnets.

Every magnet has two ends called poles:

  • North pole (N pole) — usually marked in red or labeled "N"
  • South pole (S pole) — usually marked in blue or labeled "S"

Magnetism is always bipolar, which means both poles always exist together. You cannot have a north pole without a south pole, or vice versa. If you cut a bar magnet in half, you don't get separate north and south poles — instead, you get two smaller magnets, each with its own north and south pole.

Forces Between Magnetic Poles

When two magnets are brought close together, there is a force between them. This force can either attract (pull together) or repel (push apart):

  • Like poles repel — two north poles will push each other away; two south poles will also push each other away.
  • Opposite poles attract — a north pole and a south pole will pull towards each other.

This attraction or repulsion happens without the magnets needing to touch each other. This is called a non-contact force.

Important: Magnetic forces are strongest at the poles of the magnet.

Magnets and Magnetic Materials

There is an important difference between a magnet and a magnetic material:

  • A magnet can attract or repel other magnets (depending on which poles are facing each other).
  • A magnetic material (like a piece of iron that is NOT a magnet) will always be attracted to a magnet, no matter which pole of the magnet is brought near it. It will never be repelled.

How to tell if something is a magnet or just a magnetic material:

  • If it is repelled by a known magnet, it must be a magnet itself.
  • If it is attracted to a known magnet but never repelled, it is a magnetic material (not a magnet).
  • If it is neither attracted nor repelled, it is a non-magnetic material.

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