4.2.3.2 Electricity

Spec reference: 4.2.3 (subtopic).

What you need to know

• electricity is generated by burning fossil fuels and nuclear. The UK is trying to increase the amount of
• renewable energy resources. The governments are aware that non-renewable energy resources are running out; targets of renewable resources have
• been set. Electric and hybrid cars are also now on the market.
• However, changing the fuels we use and building renewable power plants cost money. Many people are against the building of the plants near them
• and do not want to pay the extra in their energy bills. Hybrid and electric cars are also quite expensive.
• Energy Resource Advantages Disadvantages
• solar – using sunlight Renewable, no pollution, in sunny countries it
• is very reliable.

Self-assessment (checklist)

• I can recall the colour of the live wire in a three-core
• I can recall the colour of the neutral wire in a three-core
• I can recall the colour of the earth wire in a three-core
• I can state the purpose of the live wire.
• I can state the purpose of the neutral wire.
• I can state the purpose of the earth wire.
• I can recall the potential difference between the live wire
• I can explain that a live wire may be dangerous even when a
• I can solve problems for circuits which include resistors in

Key steps (method)

• Identify what the question is testing and use the correct equation/definition.
• Show substitutions and units clearly.

Common mistakes

• Unit conversions, rearranging errors, or quoting a law without applying it.