sound waves

• Wave


  A disturbance that transfers energy through a medium or space without the transfer of matter
• Sound is caused by vibrating objects
• Longitudinal Wave


  The oscillations are parallel to the direction of travel
• How a sound begins


  A sound wave begins with a vibration
• Medium can be solid, liquid or gas
• Compression


  An area of high pressure
• Gas particles in the air are easily compressed, the air particles get squashed together
• Sound travels through solids and liquids as well as gases
• Medium that sound travels fastest through

  Solid, as the particles are closest together. It travels slowest through a gas.
• Typical speed of sound through air is 330 m/s, in water is 1480 m/s, and in steel is 3150 m/s
• How we are able to hear the noise from the class next door

  The students' talk creates compressions and rarefactions sending sound waves through the air

  These travel at 330 m/s

  When the sound hits the wall it causes the wall to vibrate

  The sound wave then travels quickly through the wall as the particles are closer together

  This causes the air on the other side of the room to vibrate and the sound wave slows down as the particles are further apart

  The sound wave then vibrates certain parts of your ear which then convert it into an electrical signal that is sent to the brain
• Humans can hear frequencies between 20 – 20,000 Hz