An electric toaster has a metal outer casing, while an electric hairdryer has a plastic outer casing (and is double-insulated). Both are connected to the mains supply. Which statement correctly explains the safety requirements for these two appliances?
The toaster requires an earth wire connected to its metal casing, whereas the hairdryer only needs a two-core cable because its plastic casing is an insulator.
Both appliances require an earth wire connected to their outer casings to prevent electric shocks.
The hairdryer requires an earth wire to prevent static charge build-up, whereas the toaster is double-insulated.
Neither appliance requires an earth wire as long as they are both fitted with a fuse of the correct rating.
135 exam-style questions on CIE IGCSE Physics Electrical safety, covering Electrical safety. Each one has a worked solution and a mark scheme showing where the marks go.