Electricity in the Home

• What is the frequency of UK mains electricity?

  50 Hz
• What is the voltage of UK mains electricity?

  Around 230 V
• What are the two types of electricity supply?

  • Alternating Current (AC)
  • Constantly changes direction
  • Produced by alternating voltage
  • Used in mains supply
  • Direct Current (DC)
  • Always flows in the same direction
  • Produced by direct voltage
  • Supplied by batteries
• What type of current is used in mains supply?

  Alternating Current (AC)
• What is the purpose of the brown wire in a three-core cable?

  Provides alternating potential difference
• What does the blue wire in a three-core cable do?

  Completes the circuit
• What is the function of the green and yellow wire in a three-core cable?

  Stops appliance casing becoming live
• What potential difference is associated with the brown wire?

  230 V
• What happens when there is a connection between the live wire and the earth?

  It can be dangerous and cause a fire
• What can electric shocks cause?

  Injury or even death
• Is there a risk of electric shock even when a plug socket is turned off?

  Yes, there is still danger
• What is the large potential difference produced across the body during an electric shock?

  230 V
• When does current flow through the earth wire?

  When there’s a fault
• How does alternating current (AC) differ from direct current (DC)?

  AC changes direction; DC flows one way
• If a device is connected to a live wire, what is the risk if the insulation is damaged?

  It can cause electric shock or fire