Properties of sound waves: Waves: Physics: GCSE (9:1)

• Sound wave


  Longitudinal waves that cause particles to vibrate parallel to the direction of wave travel

  
• Medium


  A material through which a wave can be transmitted

  
• Mediums that sound can travel through

  Sound can travel through solids, liquids and gases

  
• Speed of sound


  Depends on the medium that the sound is travelling through

  
• Speed of sound in air

  Approx. 330 metres per second (m/s)

  
• Speed of sound in a vacuum

  Sound cannot travel through a vacuum because it needs particles to vibrate
• How the ear allows sounds to be heard

  Sound waves cause the ear drum and other parts to vibrate which causes the sensation of sound

  
• Frequency of a sound wave

  Related to the pitch of a sound

  
• Relationship between frequency and pitch

  The higher the frequency, the higher the pitch

  
• Amplitude of a sound wave


  Related to the loudness of a sound

  
• Relationship between amplitude and loudness

  The higher the amplitude, the louder the sound

  
• Range of human hearing

  20 Hz to 20,000 Hz

  
• Ultrasound

  Sound waves that have a frequency higher than the upper limit for human hearing (above 20,000 Hz)

  
• Infrasound

  Sound waves that have a frequency lower than the lower limit for human hearing (below 20 Hz)