Series Circuits

• Series Circuits


  Components are connected in a line, end to end, between the +ve and -ve of the power supply (except for voltmeters, which are always connected in parallel, but they don't count as part of the circuit)
• Series Circuits


  • If you remove or disconnect one component, the circuit is broken and they all stop
  • Very few things are connected in series in practice
• Using series circuits to measure quantities and test components


  1. Design series circuits

  2. Measure quantities

  3. Test components
• More cells in series

  Bigger potential difference, provided the cells are all connected the same way
• Total Potential Difference in series circuits


  Shared between the various components
• In series circuits, the total potential difference of the supply is shared between the various components
• In series circuits, the same current flows through all components
• Current in series circuits

  Determined by the total potential difference of the cells and the total resistance of the circuit: i.e. I=V÷R
• Resistance in series circuits

  The total resistance is just the sum of the individual resistances
• Adding a resistor in series

  The two resistors have to share the total potential difference, so the potential difference across each resistor is lower, and the current through each resistor is also lower. This means the total resistance of the circuit increases.
• The bigger a component's resistance

  The bigger its share of the total potential difference