Sound Waves

• Sound waves


  Vibrations of objects passed through the surrounding medium as a series of compressions and rarefactions
• Sound waves


  • Caused by vibrating objects
  • Travel faster in solids than liquids, and faster in liquids than gases
  • Cause particles in solids to vibrate when travelling through
• Sound can't travel in space because it's mostly a vacuum (there are no particles to move or vibrate)
• How we hear sound

  1. Sound waves reach eardrum and cause it to vibrate

  2. Vibrations passed to ossicles, semicircular canals and cochlea

  3. Cochlea turns vibrations into electrical signals sent to brain
• Hearing range


  Humans can hear sound in the range of 20 Hz-20 kHz
• Human hearing is limited by the size and shape of our eardrum, as well as the structure of all the parts within the ear that vibrate to transfer the energy from the sound wave
• Sound waves


  • Can be reflected by hard flat surfaces (echoes)
  • Can refract as they enter different media, speeding up when entering denser material
• Since sound waves are always spreading out so much, the change in direction due to refraction is hard to notice under normal circumstances