The core of an electromagnet needs to be magnetised and demagnetised quickly as the electrical current is switched on and off.
Which row shows the correct material to use for the core and the correct reason for this choice?
Material: soft iron; Reason: easy to demagnetise
Material: soft iron; Reason: hard to demagnetise
Material: steel; Reason: easy to demagnetise
Material: steel; Reason: hard to demagnetise
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.