Sound, hearing & the ear

• What is the function of the ear ?

  Change sound energy into electrical signals which are sent to the brain
• The middle ear contains three small bones called ossicles that transmit vibrations from the eardrum to the inner ear.
• The pinna collects sounds and directs them towards the eardrum.
• What is the smallest bone in the body ?

  Stirrup
• 3 bones in the ear

  Hammer, anvil, stirrup
• When the hammer moves it causes the anvil to move as well. This movement then makes the stirrup move. The stirrup sits on top of the oval window so its movements cause this membrane to bulge outwards.
• The air inside the ear canal starts to vibrate and the ear drum vibrates. The ear drum passes the vibrations onto the ear bones and the liquid inside the cochlea vibrates and electrical signals are sent to the brain along the nerve
• How does sound travel?

  In waves or vibrations
• Sound waves can travel through solids
• Sound travels much faster through the ground than the air
• The speed of sound is 330m in the air.
• What are sound waves measured in ?

  Hertz (Hz)
• High pitch waves are...


  close together
• Low pitch waves are...

  Far apart
• Loud sounds are..


  Tall
• Quiet sounds are...


  Short