Series and parallel circuits

• There are two ways of joining electrical components, in series and parallel. Some circuits include both series and parallel parts.
• For components connected in series:

  • There is the same current through each component
  • the total potential difference of the power supply is shared between the components
  • the total resistance of two components is the sum of the resistance of each component: R total = R1 + R2 (ohms)
• For components connected in parallel:

  • the potential difference across each component is the same
  • the current through the whole circuit is the sum of the currents through the separate components
  • the total resistance of two resistors is less than the resistance of the smallest individual resistor.
• Ammeters should be connected in series with the component that they are measuring current through
• Voltmeters should be connected in parallel to the component that they are measuring the potential difference of.
• It’s advantageous to connect lamps in parallel because if one lamp blows, the rest will be unaffected and can still receive current