Mains Electricity 10.4

These flashcards cover key concepts from the Edexcel GCSE Physics 10.4 Mains Electricity lecture.

What is direct current (DC)?

A current that is steady, flowing in the same direction from positive to negative.

What is the frequency of alternating current (AC) in the UK?

50 Hz.

What is the potential difference of mains electricity in the UK?

Around 230 V.

What are the functions of the live and neutral wires in mains electricity?

The live wire carries the alternating potential difference; the neutral wire completes the circuit.

What color is the live wire in a three-core cable?

Brown.

What color is the neutral wire in a three-core cable?

Blue.

What color is the earth wire in a three-core cable?

Green and yellow stripes.

What is the purpose of the earth wire?

To provide a low resistance path to earth, preventing electrical shock.

What do fuses and circuit breakers do?

They cut off the flow of electricity to an appliance if the current becomes too large.

What happens when a live wire touches a metal casing without an earth wire?

The case becomes electrified, posing a risk of electrocution.

Why do electricians switch off the mains electricity when working with appliances?

To avoid the risk of electric shock from live wires.