Which of the following methods can be used to demagnetise a steel bar magnet?
Stroking it repeatedly in one direction with the north pole of a magnet.
Placing it inside a solenoid connected to an alternating current (a.c.) supply and slowly withdrawing it.
Protecting it from external magnetic fields by storing it with iron keepers.
Placing it inside a solenoid connected to a direct current (d.c.) supply and gradually increasing the current.
169 exam-style questions on CIE IGCSE Physics Simple phenomena of magnetism, covering Simple phenomena of magnetism. Each one has a worked solution and a mark scheme showing where the marks go.