Electricity Circuits

• Circuits can be series or parallel circuits
• Series circuit


  • If one bulb breaks, all go off
  • Current is the same everywhere
  • More bulbs make them dimmer
• Parallel circuit


  • If one bulb breaks, others stay on
  • Current splits at branches
  • More bulbs stay bright
• Electricity can be dangerous if not used properly
• Electricity dangers


  • Fires
  • Burns
  • Shocks that can stop heart or lungs
• Cables have three colour-coded inner wires
• Inner wires


  • Live wire (brown)
  • Neutral wire (blue)
  • Earth wire (green and yellow)
• Cell symbol

  
• Bulb symbol:

  
• Ammeter symbol:

  
• Open Switch symbol:

  
• Closed switch symbol:

  
• Resistor symbol:

  
• Voltmeter symbol:

  
• Fuse symbol:

  
• Variable resistor symbol:

  
• A series circuit

  • If one bulb breaks then all the other go off
  • The current is the same everywhere
  • If you add more bulbs, they will be dimmer because it is harder for the electricity to get through.
  • The resistance of the circuit is higher with more bulbs

  
• Parallel circuit

  • If one bulb breaks the other bulbs stay on
  • The current splits up when it comes to a branch. The current in all the branches adds up to the current in the main circuit
  • If you add more bulbs, they stay bright. It is easier for the current to flow with more branches.

  
• Fuses are used in plugs and show a rating of the current that can be passed through them. If the wrong fuse is used it could melt.
• Circuit breakers cut off the current if it gets to high. They protect the ring mains in building (loops of parallel circuits)
• A plug has 3 wires: Earth, neutral and live

  
• Circuits can be series or parallel circuits
• Series circuit


  • If one bulb breaks, all go off
  • Current is the same everywhere
  • More bulbs make them dimmer
• Parallel circuit


  • If one bulb breaks, others stay on
  • Current splits at branches
  • More bulbs stay bright
• Electricity can be dangerous if not used properly
• The carbon cycle

  
• Electricity dangers


  • Fires
  • Burns
  • Shocks that can stop heart or lungs
• Wiring in houses


  • Designed to be safe
  • Fuses melt if current gets too high
  • Circuit breakers cut off current if too high
• Cables have three colour-coded inner wires
• Inner wires


  • Live wire (brown)
  • Neutral wire (blue)
  • Earth wire (green and yellow)