Core · Practice questions · Magnetic poles

Poles, forces, and the sure test.

Six original Cambridge-style questions on magnetism: the like and unlike rule, magnetic materials, induced magnetism, and why only repulsion proves a magnet.

Original questions All questions on this page are original work, written in the Cambridge IGCSE style. They are not from past papers. They test the same concepts and skills the syllabus rewards.
The reasoning that earns the marks

Repulsion is the only sure test.

01
Recall
[2 marks]

State what happens when each of the following pairs of poles is brought close together.

(a) A north pole and a north pole.
(b) A north pole and a south pole.

(a) They repel (push apart). ✓

(b) They attract (pull together). ✓

like poles repel, unlike poles attract

02
Recall
[2 marks]

Name two metals that are attracted to a magnet, and state one common metal that is not.

  • Attracted: any two of iron, steel, cobalt, nickel. ✓
  • Not attracted: copper (or aluminium, brass, gold). ✓
03
Analysis
[3 marks]

An unmagnetised iron nail is brought near the north pole of a strong magnet, and the nail is attracted to it.

(a) Name the effect that lets the nail be attracted even though it is unmagnetised.
(b) State which pole is induced in the end of the nail nearest the magnet, and explain why.

(a) Induced magnetism. ✓

(b) A south pole is induced in the near end. ✓

The induced pole is opposite to the approaching north pole, so unlike poles face each other and the nail is attracted. ✓

04
Analysis
[3 marks]

A bar is brought near a known magnet. When one pole of the magnet is offered, the bar is pushed away.

(a) State whether the bar is definitely a magnet.
(b) Explain your answer.

(a) Yes, it is definitely a magnet. ✓

(b) The bar was repelled, and only like poles repel each other. ✓

An unmagnetised material can only be attracted, never repelled, so repulsion proves the bar has its own pole. ✓

05
Analysis
[3 marks]

Two identical-looking steel bars, P and Q, are both attracted to each other whichever way round they are held. A student claims this proves both are magnets.

State whether the student is correct, and explain what the observation does and does not tell you.

  • The student is not correct. ✓
  • Attraction every way round is also what happens if only one bar is a magnet and the other is unmagnetised steel, by induced magnetism. ✓
  • To prove both are magnets, the student must find an orientation in which they repel. ✓

attraction alone is never a sure test

06
Analysis
[2 marks]

Two magnets are held with their north poles facing each other. Describe how the force between them changes as they are pushed closer together, and name the type of force.

  • The poles are alike, so the force is a repulsion that gets stronger as they get closer. ✓
  • It is a non-contact force (it acts without the magnets touching). ✓

Mark this once you have attempted all six and checked your working. It records a Practiced badge on the topic and adds a one-time bonus. Revealing the solutions alone does not count.