Electromagnetic Waves

• All EM waves are transverse, which transfer energy from a source to an absorber
• All EM waves travel at the same speed through the air or a vacuum
• EM waves form a continuous spectrum over a range of frequencies
• EM spectrum

  • Radiowaves (1m-10^4m)
  • Microwaves (10^-2m)
  • Infrared (10^-5m)
  • Visible light (10^-7m)
  • Ultra violet (10^-8m)
  • X-Rays (10^-10m)
  • Gamma rays (10^-15m)
• EM uses

  • Radiowave - Telecommunications
  • Microwave - Radar, cooking, phones and satellites
  • Infrared - Remote controls, heat sensors, night vision, cameras and heat cameras
  • Visible light - Fibre optic cables and seeing things
  • Ultraviolet - Suntan, checking forgeries, CSI and pollination
  • X-ray - Medical and airport security
  • Gamma - Treating cancer, sterilisation
• EM Dangers

  • Radio wave - None
  • Microwave - Burns and cataracts, potentially cancer
  • Infrared - Can burn
  • Visible light - Eye damage
  • Ultra violet - Skin cancer
  • X-ray - Cancer and cell mutation
  • Gamma - Cancer and cell mutation