Potential difference in Parallel circuits

• Potential difference


  Tells us about energy transfers taking place in a circuit. One volt of potential difference means one Joule of energy is transferred for each Coulomb of charge moving through the circuit.
• In a series circuit, potential difference is split between components.
• Parallel circuit


  Has branches, and some of the current passes through each branch.
• In a parallel circuit, the potential difference across each component is the same.
• Measuring potential difference in a parallel circuit

  1. Use a voltmeter across the cell

  2. Use a voltmeter across the branches
• Potential difference measurements in a parallel circuit

  • Cell potential difference is 6 volts
  • Top lamp potential difference is 6 volts
  • Bottom lamp potential difference is 6 volts
• When components are connected in parallel


  The potential difference across each component is the same
• Calculating potential difference in a parallel circuit

  • Potential difference across top lamp is 12 volts
  • Potential difference across bottom lamp is 9 volts (2 volts + 7 volts)
• You'll find plenty more questions on potential difference in parallel circuits in the Vision workbook.