1. Sound Waves & Hearing
How do we Hear Sounds??

2. Essential Standard
6.P.1Understand the properties of waves and the wavelike property of energy in earthquakes, light and sound waves.

3. Clarifying Objective
6.P .1.3Explain the relationship among the rate of vibration, the medium through which vibrations travel, sound and hearing.

4. Essential Questions
How does sound travel through the mediums of solids, liquids, & gasses?
How is the human ear designed to receive sound waves?
How do vocal chords work to produce sound?

5. EOG Questions
What is the relationship between the speed of sound and the medium through which it passes?
If a guitar player adds thicker strings how will it effect the vibrations of the strings?

6. Waves
Waves are a disturbance or vibration a way of transferring ENERGY from one place to another
They transport ENERGY from on place to another
There are different categories & types of waves
They all have their own characteristics that make them waves

7. What is Sound
Sound is vibrations of energy that travel through a medium and can be heard and processed by human or animal ears
Vibrations
Travel through a medium
Solid
Liquid
Gas
Heard and processed by humans or animals

8. Mechanical Waves
Mechanical Waves are waves that require a solid, liquid or gas to move through
Transversal Waves
Longitudal Waves

9. Longitudinal Waves
Longitudinal Waves are like pinball waves. These waves vibrate in the direction of the flow of energy
An example is a pinball machine
2:48-3:47

10. How is Sound Created Sound Starts when an object is vibrated
The vibrations send out energy in a Longitudinal wave through a medium
The energy travels through either liquids, solids, or gases

11. Traveling through Mediums
Sound waves are mechanical waves meaning they must travel through a medium (unlike Electromagnetic Waves)
Solid
Liquid
Gas

12. Traveling Sound Sound travels fastest through solids
It travels at a medium speed through liquids
Sound travels slowest through gases
2:53-3:40

13. Essential Questions Get with a partner and answer…
How does sound travel through the mediums of solids, liquids, & gasses?

14. Particles Vibrating
Next particles (atoms) crash into each other sending a chain reactions to the next particle & so on

15. Atoms/Energy Hits the Ear
The particles of atoms/energy crash into each other until they hit the human ear
The outer ear catches these atoms/energy and helps us determine…
Direction
Frequency

16. Hitting the Ear Drum
The sound waves then travel down the ear canal and hit the ear drum
The ear drum begins to vibrate from the repeated atoms/energy hitting it

17. Milieus
The vibrating ear drum then hits the first of three very small bones in the inner ear (smallest bones in the body)
This bone is called the Milieus which is attached to the ear drum
It is attached to the next bone and sends the vibration through

19. Incus The vibration then hits the Incus
The Incus is the middle bone in the inner ear
The Incus transfers the vibration of energy to the last of the 3 inner ear bones

20. Stapes
The sound vibration is then sent to the last of the inner ear bones called the Stapes
The Stapes hits the side/wall of the cochlea and sends sound waves

21. Cochlea
Inside the Cochlea there are about 20,000-30,000 little fibers that are kind of like blades of grass
These fibers are set to only recognize certain frequencies
When the specific frequency hits the specific fiber it sends a signal to tiny hair cells

22. Cochlea
The tiny hair cells take the specific frequency to the Cochlear nerve
The Cochlear nerve then sends that frequency to the brain
The Brain identifies the sound and puts a name to the sound

23. How we Hear http://www.youtube.com/watch?v=_pcsOG-H3Ac 8:32-9:00

24. Essential Questions Get with a partner and answer…
How is the human ear designed to receive sound waves?