sound waves

• Sound waves


  Longitudinal waves that cause air particles to vibrate from side to side
• How sound waves are transmitted from one medium to another

  1. Sound waves in air cause vibrations

  2. Vibrations are transmitted to a solid medium (e.g. microphone cone, eardrum)

  3. Solid medium vibrations are converted to electrical signals or sensations of sound
• Human hearing frequency range

  • 20 Hertz to 20,000 Hertz
  • Frequencies outside this range may not cause eardrum vibration
• Wave speed


  The speed at which a wave travels, equal to the frequency multiplied by the wavelength
• Frequency does not change when a wave changes medium
• Frequency


  Determines the pitch of a sound - higher frequency = higher pitch
• Amplitude


  Determines the loudness of a sound - higher amplitude = louder sound
• Sound waves can only move through a medium (e.g. air, solid)
• Sound waves can be reflected, creating an echo