Domestic electricity and safetyIB MYP Physics: Mind map

Exam questions on Domestic electricity and safety

1. A family in Abu Dhabi buys an electric kettle with a metal casing. The kettle has a three-pin plug fitted with a fuse and is connected to the mains supply.
   Explain why the metal casing of the kettle is connected to the earth wire.2 marks
2. A hair salon in Dubai uses a hairdryer that normally draws a current of 8 A from the 230 V mains supply. The plug can be fitted with a 1 A, 3 A, 5 A or 13 A fuse.
   Explain how a fuse protects the hairdryer circuit.2 marks
3. A school workshop in Singapore has a power drill with a plastic casing and a two-core cable with no earth wire. The workshop's consumer unit (fuse board) uses circuit breakers instead of fuses.
   Explain how double insulation protects the user of the drill even though it has no earth wire.3 marks