Magnets Questions & MCQ — Practice with Answers

What is a magnet?

A magnet is an object that can attract materials made of iron, steel, cobalt, or nickel. These materials are called magnetic materials. Magnets come in different shapes — bar magnets, horseshoe magnets, ring magnets, and button magnets — but they all behave the same way.

Magnetic vs non-magnetic materials

Magnetic materials are attracted to magnets. They include iron, steel, cobalt, and nickel. Non-magnetic materials are not attracted to magnets. Examples include wood, plastic, rubber, glass, copper, aluminium, and gold. It is important to remember that not all metals are magnetic — only iron, steel, cobalt, and nickel are.

Poles of a magnet

Every magnet has two poles: a North pole (N) and a South pole (S). The poles are where the magnetic force is the strongest. There are two key rules about how poles interact:

• Like poles repel: North–North or South–South push each other away.
• Unlike poles attract: North–South pull towards each other.

A freely suspended magnet will always come to rest pointing in the North–South direction. This is how a compass works — its magnetic needle is a small magnet.

Making magnets

There are two main ways to make a magnet:

• Stroking method: Stroke a piece of iron or steel repeatedly in the same direction with one pole of a magnet. After many strokes, the iron or steel becomes magnetised.
• Using electricity (electromagnets): Wrap a wire around an iron nail and connect it to a battery. When the current flows, the nail becomes a magnet. An electromagnet can be switched on and off — unlike a permanent magnet.

Uses of magnets in everyday life

Magnets are used in many everyday objects and situations:

• Compasses use a magnetic needle to find direction.
• Fridge magnets hold notes and pictures on a steel refrigerator door.
• Magnetic catches keep cupboard doors shut.
• Electromagnets are used in cranes to lift heavy iron and steel objects, in doorbells to make the bell ring, and in MRT trains.

“All metals are magnetic.” This is one of the most common mistakes. Only iron, steel, cobalt, and nickel are magnetic. Many metals — including copper, aluminium, gold, and silver — are not attracted to magnets at all. If PSLE asks whether a copper coin is attracted to a magnet, the answer is no.

“Bigger magnets are always stronger.” The strength of a magnet does not depend on its size alone. A small, strong magnet can attract more objects than a large, weak magnet. The strength depends on the material the magnet is made of and how it was magnetised.

“Magnets attract all shiny objects.” Shininess has nothing to do with whether an object is magnetic. Aluminium foil is shiny but not magnetic. A rusty iron nail is not shiny but is still attracted to a magnet. Always test by material — not by appearance.

“A magnet can repel iron or steel.” A magnet can only repel another magnet. A magnet always attracts magnetic materials like iron and steel — it can never repel them. Repulsion only happens between two magnets when like poles face each other.