Potential diff

• What is required for a current to flow in a circuit?

  A cell or other power source
• How do chemical reactions in a cell contribute to current flow?

  They release energy that allows a current to flow around the circuit
• What does the potential difference of a power source measure?

  The work it does to make a current flow around a circuit
• In what unit is potential difference measured?

  Volts (V)
• What happens to charge carriers when the potential difference of the cell increases?

  They have more energy and do more work
• What is an example of a potential difference in a circuit?

  A 6V cell
• What does the potential difference across a component measure?

  The work charge carriers do when passing through it
• How does the potential difference across the lamp relate to the energy given by the cell?

  If all energy is passed to the lamp, the potential difference across it is also 6 volts
• Why is it important to specify the potential difference across a lamp?

  To clarify that it is not the potential difference of the lamp itself
• What term is often used interchangeably with potential difference?

  Voltage
• How do we measure potential difference?

  Using a voltmeter
• What is the symbol for a voltmeter in a circuit?

  A circle with a V inside
• How should a voltmeter be connected to measure potential difference?

  In parallel to the component it is measuring
• What does it mean for components to be in parallel in a circuit?

  They are on separate branches with no path around the circuit passing through both
• How would you connect a voltmeter to measure the potential difference across a lamp?

  Connect it in parallel with the lamp
• What is the relationship between potential difference and energy in a circuit?

  • Potential difference measures the work done by charge carriers
  • Higher potential difference means more energy is given to components
  • Energy from the cell is transferred to charge carriers, then to components like lamps
• What features do voltmeters have for measuring potential difference?

  • Can have analog or digital displays
  • Current flows through positive to negative connections
  • Needle movement indicates energy of charge carriers
• What is the purpose of Launchpad Learning's Smart Learning platform?

  • Covers entire specifications for exams
  • Provides interactive quizzes and videos
  • Offers support from an AI tutor