Domestic Uses and Safety

Cards (16)

  • Is mains electricity an a.c supply or a d.c supply?
    1. c supply
  • What does a.c. stand for?
    Alternating Current
  • What does d.c. stand for?
    Direct Current
  • Define alternating current and direct current.
    • Alternating current: Changes direction at a specific frequency
    • Direct current: One directional current flow
  • What is the frequency of the UK mains electricity supply?
    50 Hz
  • What is the voltage of the UK mains electricity supply?
    230V
  • How many wires are usually in the cables connecting electrical appliances to the mains?
    Three wires
  • Name the wires in the cables connecting electrical appliances to the mains.
    1. Live wire
    2. Neutral wire
    3. Earth wire
  • What is the insulation colour used on the Earth wire?
    Green and Yellow Stripes
  • What is the insulation colour used on the live wire?
    Brown
  • What is the insulation colour used on the neutral wire?
    Blue
  • Explain when the Earth wire does and doesn’t carry a current.
    • No current flows under normal circumstances
    • Current flows if a fault occurs (e.g., surge)
  • What potential is the neutral wire at?
    0 Volts
  • What is the potential difference between the live and earth wires?
    230 Volts
  • What is the purpose of the neutral wire?
    To complete the circuit back to mains
  • For metal appliances, where is the Earth wire connected to and why?
    • Connected to the metal casing
    • Prevents electrocution if live wire touches casing