electricty

• what are the characteristics of each wire

  • copper coated to conduct electricty
  • different coloured plastic coating to represent what each wire does
• what are the colours of each wire

  live wire - brown

  neutral - blue

  earth - yellow and green
• what does the live wire do


  • the live wire carries the mains electricities alternating potential difference of 230 volts and produces a current to the appliance
• what does the neutral wire do

  the neutral wire completes the circuit and carries current out of the device.current in from live and out from neutral.The neutral wire has a potential difference of 0
• what does the earth wire do

  the earth wire carries away the current from the casings Incase something goes wrong and it's at 0 volts
• why can u get a shock even if the socket is turned off(casing is live)

  • the human body is at 0v
  • body provides a link between the supply and earth
  • a large potential difference is produced through your body as current flows through you
  • this leads to a large electric shock which could kill you.
• How does an earth wire (earthing) protect us from an electric shock

  • earth wire is connected to the casing of the case
  • if the live wire touches the casing the earth wire provides an alternative current away preventing an electric shock
• how does double insulation protect us from an electric shock

  • double insulation is where a material is coated ion plastic which protects it from doesn't conduct an electricity and protects it from an electric shock therefore an earth wire isn't needed
• How does a fuse work and it's disadvantages

  A fuse is a thin piece of wire between the live wirea fuse works when the current between an appliance is too high (surge) the current fuse wire heats up and melts which breaks the circuit

  advantages - cheap

  disadvantage - permentaly breaks and needs to be replaced
• How does a circuit breaker work and why is it better than fuse

  • a circuit breaker works by tripping the circuit (opening the circuit and breaking the flow of current) when there is a surge causing the surge to turn off however it doesn't;t break so it can be reinstated and repeated making it better than a fuse but more expensive
• what is a surge

  • a sudden increase in current which can lead to fires or an electric shock and is caused by a faulty error in the circuit or when the appliance has been recently turned off