Which statement describes the primary function of an earth wire in an electrical appliance with a metal casing?
to reduce the total electrical resistance of the circuit
to prevent the metal casing from becoming live and causing a shock if a fault occurs
to increase the current flowing through the device under normal conditions
to store excess electrical energy when the appliance is turned off
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.