Radio Waves (OCR GCSE Physics A (Gateway))

Radio Waves

Higher Tier Only

• 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

  • These radio waves produce, or can themselves induce oscillations in electrical circuits

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