RECAP THE CONCEPTS

• Electricity is able to flow through wires in a closed circuit.

  
  

• Electricity cannot flow through an opened circuit. This happens when there is a gap in the circuit (e.g. if the bulb is fused or the switch is open).

  
  

• All metals are electrical conductors, whereas most non-metals (e.g. glass, rubber) are electrical insulators.

Bulbs arranged in series

• When additional bulbs are added in series, the brightness of each bulb decreases.

  
  
  
  

• If 1 bulb fuses, the other bulbs will not light up.

  
  
  
  

• The bulbs cannot be controlled independently.

Bulbs arranged in parallel (usually better than bulbs arranged in series)

• When additional bulbs are added in parallel, the brightness of each bulb remains the same.

  
  
  

• If 1 bulb fuses, the other bulbs will remain lit.

  
  
  

• The bulbs can be controlled independently using different switches.