An electromagnet is to be constructed. A core material is needed that becomes magnetic when a current flows in the coil, but loses its magnetism quickly when the current is switched off.
Which row gives the correct material to use for the core and the correct reason for choosing this material?
Material: steel; Reason: easy to demagnetise
Material: steel; Reason: hard to demagnetise
Material: soft iron; Reason: easy to demagnetise
Material: soft iron; 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.