Learning objective

Understand that a mains circuit includes a live wire, a neutral wire, and an earth wire, and describe why the switch should be connected to the live wire to safely turn off the circuit.

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Cambridge IGCSE PhysicsElectricity and magnetismCore content

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Understand that a mains circuit includes a live wire, a neutral wire, and an earth wire, and describe why the switch should be connected to the live wire to safely turn off the circuit

This point belongs to Electrical safety, especially Electrical safety outcomes.
You need to be able to understand that a mains circuit includes a live wire, a neutral wire, and an earth wire, and describe why the switch should be connected to the live wire to safely turn off the circuit.
The key ideas to know are Know and Explain.
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This objective helps connect Electrical safety outcomes to exam-style questions, flashcards, and revision notes for Electrical safety.

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Description

Mains Circuit Components

A mains circuit consists of a live wire, a neutral wire, and an earth wire. The live wire carries current to the appliance, the neutral wire returns the current, and the earth wire provides a safety path for excess current.

a
State Name the three wires in a mains circuit.
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[1]

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