Potential difference in Series

• What should you be able to explain by the end of the video?

  Potential difference
• What is electric current described as?

  A flow of electrons around a circuit
• What happens to electrons in a circuit?

  They move out of the cell and return
• Why does the lamp light up in the circuit?

  Electrons give the lamp energy
• What are the energy transfers involved in the circuit?

  • Chemical energy from the cell
  • Transferred to electrical energy
  • Converted to light and thermal energy in the lamp
• What is another term for potential difference?

  Voltage
• What does a potential difference of one volt indicate?

  One Joule of energy per Coulomb of charge
• How do we measure potential difference?

  Using a voltmeter
• What does a voltmeter measure in the circuit?

  The potential difference across components
• How do you measure the potential difference of a cell?

  Place the voltmeter across the cell
• What was the reading of the voltmeter across the cell?

  9 volts
• What does a reading of 9 volts indicate about energy transfer?

  Nine Joules of energy per Coulomb of charge
• What is the potential difference across the lamp in the circuit?

  Also 9 volts
• How does potential difference affect the brightness of lamps in series?

  • Total potential difference remains the same
  • Shared between lamps
  • Each lamp is dimmer than a single lamp
• What happens to the brightness of lamps when they are in series?

  Both lamps are dimmer than one lamp
• What is the potential difference across each lamp in a series circuit with two identical lamps?

  4.5 volts
• Why are the lamps dimmer in a series circuit?

  Energy is shared between the lamps
• What is the potential difference across two different lamps in series?

  Sum equals the cell's potential difference
• What is the potential difference of the first lamp in the example?

  6 volts
• What is the potential difference of the second lamp in the example?

  3 volts
• What does the total potential difference across both lamps equal?

  The potential difference across the cell
• What are the key points about potential difference in series circuits?

  • Total potential difference is constant
  • Shared among components
  • Affects brightness of lamps
• Where can you find questions on potential difference in series circuits?

  In the vision workbook
• What should you be able to describe after watching the video?

  Potential difference in series circuits