Potential Difference in Parallel Circuits

• What does potential difference tell us about in a circuit?

  Energy transfers taking place in a circuit
• What does a potential difference of one volt mean?

  One Joule of energy per Coulomb of charge
• How much energy does the current carry per Coulomb of charge in the series circuit?

  9 Joules
• How is potential difference distributed in series circuits?

  It is split between components
• What is a characteristic of parallel circuits?

  They have branches
• How can you measure potential difference across a cell?

  Using a voltmeter
• What is the potential difference across each branch in a parallel circuit?

  It is the same for each component
• If the potential difference across the bottom lamp is 12 volts, what is the potential difference across the top lamp?

  12 volts
• If the potential difference across the top lamp is 12 volts, what is the potential difference across the cell?

  12 volts
• What is the potential difference across the right-hand lamp if it is 7 volts?

  7 volts
• What are the key facts about potential difference in parallel circuits?

  • Potential difference across each component is the same
  • Measured using a voltmeter
  • Total potential difference remains constant across branches
• How do you calculate potential difference in parallel circuits?

  1. Identify the potential difference across the cell
  2. Recognize that it is the same across all branches
  3. Use voltmeters to measure across components