Radio Waves (AQA GCSE Physics: Combined Science)

• Radio waves can be produced by connecting an antenna to a high frequency alternating current (a.c.) power source
  • The oscillation of charge in the a.c. circuit produces radio waves with the same frequency of oscillation

Radio waves are produced by high-frequency alternating currents and induce similar currents when they are received

• In the transmitting antenna:
  • The charge from the alternating current oscillates up and down the antenna
  • This produces radio waves that can be absorbed by a similar aerial some distance away

• In a receiving aerial:
  • The metal aerial absorbs the radio waves
  • This creates an alternating current with the same frequency as the transmitted wave