Which of the following procedures is a correct method to demagnetise a permanent bar magnet?
Heating it strongly over a Bunsen burner while holding it in an east–west direction
Placing it inside a freezer at 0∘C0^\circ\text{C}0∘C
Connecting its ends to a high-capacity direct current (d.c.) battery
Wrapping it in aluminium foil and earthing it
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.