Mains electricity

• What type of current is mains electricity in the UK?

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


  50 Hertz
• What is the potential difference of mains electricity in the UK?


  Around 230 volts
• Why are electrical appliances in the UK connected using three core cable?


  To ensure safe and effective transmission of electricity
• What are the three wires in a three core cable?

  • Live wire (brown)
  • Neutral wire (blue)
  • Earth wire (green and yellow striped)
• What is the function of the live wire?


  It carries a potential difference of around 230 volts from the supply
• What is the potential difference of the neutral wire?


  Around zero volts compared to the live wire
• What is the purpose of the earth wire?


  It serves as a safety wire to prevent electric shocks
• What happens if the live wire touches the metal case of an appliance?


  The case can become live, posing a risk of electric shock
• How does the earth wire protect against electric shocks?


  It directs excess current to the ground, preventing the case from becoming live
• What happens when a live wire comes loose in an appliance with a metal case?


  The metal case can become live, leading to a potential electric shock
• What is the role of the fuse in an electrical circuit?


  It melts and shuts off the current if there is a fault
• What is the symbol for a fuse?


  A specific symbol that represents a fuse in electrical diagrams
• What are the key points to remember about mains electricity connections?

  • Mains electricity is AC with a frequency of 50 Hz and 230 volts.
  • Appliances use three core cables: live, neutral, and earth wires.
  • The live wire carries 230 volts, the neutral wire is around 0 volts, and the earth wire is for safety.
  • A fuse protects against faults by melting and cutting off the current.
• Why is it important to understand the functions of the live, neutral, and earth wires?


  To ensure safety and proper functioning of electrical appliances