Research

Research

**How does sound work?** **-Outer ear funnels in the sound.** **-Middle ear turns vibrations to solids.** **-Inner ear processes vibration for us to hear.** **-Doppler effect is when an object gets closer and the pitch gets higher.** **-When the object gets further away the pitch gets lower.** **-Echos are sound bouncing off the walls.** **-Can hear sound when asleep but the brain ignores is.** **-Sound is made by vibrations.**

**How do people hear?** **-Ear shaped like a cone.** **-Sound travels at 332 meters per second.** **-Sound travels best through solid or water.** **-Sound travels 15 times faster through steel than air.** **-Eardrum is made of a skin-like material.** <span style="font-family: 'Courier New',Courier,monospace; font-size: 110%; letter-spacing: 0px;">**-2 ears to hear all around.**

<span style="font-family: 'Courier New',Courier,monospace; font-size: 110%; letter-spacing: 0px;">**How can your hearing change?** <span style="font-family: 'Courier New',Courier,monospace; font-size: 110%; letter-spacing: 0px;">**-Gets worse in age.** <span style="font-family: 'Courier New',Courier,monospace; font-size: 110%; letter-spacing: 0px;">**-People 60 years or older can normally hear 12khz or less.** <span style="font-family: 'Courier New',Courier,monospace; font-size: 110%; letter-spacing: 0px;">**-Sound above 90dB can damage ears and hearing.** <span style="font-family: 'Courier New',Courier,monospace; font-size: 110%; letter-spacing: 0px;">**-Ears damaged by music in headphones.** <span style="font-family: 'Courier New',Courier,monospace; font-size: 110%; letter-spacing: 0px;">**-Short, loud bursts of sound can also damage hearing.**