AC/DC

• What are the two types of current mentioned?

  Alternating current (AC) and direct current (DC)
• How does alternating current (AC) behave?

  The direction of the current constantly swaps
• What causes alternating current to fluctuate?

  Alternating potential difference or voltage
• What does measuring potential difference over time show in AC?

  It fluctuates between negative and positive
• What is the frequency of UK mains supply electricity?

  50 hertz
• What is the voltage of UK mains supply electricity?

  Around 240 volts
• Why might you hear the voltage referred to as 230 volts instead of 240 volts in the UK?

  Both values are correct for exams
• How does direct current (DC) differ from alternating current (AC)?

  DC flows in the same direction constantly
• Where do we commonly find direct current (DC)?

  In cells and batteries
• What devices are used to obtain potential difference time graphs?

  Oscilloscopes
• What are the characteristics of alternating current (AC)?

  • Direction constantly swaps
  • Caused by alternating voltage
  • Fluctuates between positive and negative
  • UK mains supply: 50 Hz, ~240 volts
• What are the characteristics of direct current (DC)?

  • Flows in the same direction
  • Produced by direct voltage
  • Found in cells and batteries
• What is the purpose of an oscilloscope?

  • Displays potential difference time graphs
  • Monitors electrical signals
  • Used in various electronic applications