1. Sound Waves Compressional WaveCompressional Wave Mechanical Wave (must have a medium)Mechanical Wave (must have a medium) [http://www.ccohs.ca/images/noise1.gif] Click here for demo of mechanical properties.

2. Speed of Sound Speed of sound is constant in a given medium (chart pg. 359)Speed of sound is constant in a given medium (chart pg. 359) [http://www.angelfire.com/scifi/dschlott/sSpeed.gif]

3. Speed of Sound The speed of sound increases when the temperature is warmer.The speed of sound increases when the temperature is warmer. This is a direct relationship.This is a direct relationship.

4. Speed of Sound V in air = 331 + 0.6(T C )V in air = 331 + 0.6(T C ) Units are in m/sUnits are in m/s

5. Speed of Sound Example: How fast does a sound wave move when air temperature is 10 °C?Example: How fast does a sound wave move when air temperature is 10 °C? V = 331 + 0.6 (10)V = 331 + 0.6 (10) V = 331 + 6V = 331 + 6 V = 337 m/sV = 337 m/s

6. Speed of Sound Sonic Boom – Object is traveling faster than the speed of sound. MACH scale [http://community.webshots.com/photo/29220851/29224250NbiEGaCAdC#]

7. [http://www.grc.nasa.gov/WWW/K-12/airplane/Images/mach.gif] Click here for a Sonic Boom video

8. Sound Waves and Hearing Outer Ear – visible part of ear, ear canal and eardrum. (Pg. 361)Outer Ear – visible part of ear, ear canal and eardrum. (Pg. 361) Energy from sound waves make the eardrum vibrate.Energy from sound waves make the eardrum vibrate.

9. Sound Waves and Hearing Middle Ear – Bones called the hammer, anvil, and stirrup amplify the sound.Middle Ear – Bones called the hammer, anvil, and stirrup amplify the sound.

10. Sound Waves and Hearing Inner Ear – The cochlea sends impulses to the brain.Inner Ear – The cochlea sends impulses to the brain.

11. Sound Waves and Hearing Hearing loss is usually caused by damage to the hair cells in the cochlea.Hearing loss is usually caused by damage to the hair cells in the cochlea. [https://secure.dca.net/nohr/Nohrcontactimages/Hair-cellbk.jpg]

12. [http://www.sickkids.ca/auditorysciencelab/images/ohc_mild_sml.jpg]

13. Intensity How much energy a sound wave carries over time.How much energy a sound wave carries over time. Determines how far it can travel.Determines how far it can travel. [http://www.safetyline.wa.gov.au/institute/level2/course18/lecture54/images/noise11b.gif]

14. Loudness The human perception of intensity.The human perception of intensity. Measured in decibels (dB)Measured in decibels (dB)

15. [http://www.ednasia.com/cmsimages/issue0410cs5.gif] [http://www.hearinginseattle.com/images/decibelbars1.jpg]