Waves for detection and exploration

• what are ultrasound waves?

  waves which have a frequency higher than the upper limit of human hearing (20kHz)
• example use for ultrasound waves

  medical or industrial imaging
• what natural event causes seismic waves to be produced? what types are produced?

  • earthquakes
  • produce both P-waves and S-waves
• state a difference between the medium that P-waves and S-waves can travel through

  • P-waves travel through both solids and liquids
  • S-waves only travel through solids only
• technique used to detect objects in deep water and measure water depth

  • echo sounding
  • high frequency sound waves are emitted, reflected and detected
  • time difference between emission and detection, alongside wave speed are used to calculate distances