1. Sounds like a Turkey Happy Thanksgiving!!! -I am thankful for wonderful students

2. It’s all about vibrations! When something vibrates (like our vocal cords) the particles in the air around it start moving – This movements is called “sound waves” 1.These waves travel through the air and hit your eardrum 2.Your eardrum then sends messages to your brain 3.Your brain interprets the “message” as sound

3. What makes the different pitches The wavelength of each sound wave determines the pitch

4. Question How can you make a high sound?How can you make a low sound? Hypothesis (example: I hypothesize that snapping a thick rubber band will make a low sound) Which materials will you use to test your hypothesis? (example: a thin a thick rubber band will be used) Conclusions (were you correct? Did your experiment produce a high or low sound?) 1. How do turkeys change the pitch of their gobble?2. How do turkeys change the volume of their gobble?

5. Review: short versus long string http://pbskidsorg/designsquad/games/string_thing/msg_how_sound_works.swf Reminder: the quicker the vibration the higher the note, the slower the vibration the lower the note Short = High Long = Low

6. Review: Thin versus thick string Thin = High Thick = Low http://pbskidsorg/designsquad/games/string_thing/msg_how_sound_works.swf

7. Review: Less versus more tension http://pbskidsorg/designsquad/games/string_thing/msg_how_sound_works.swf Less tension = High More tension = Low

8. Why do they look and sound so ridiculous? Brad Allen

9. http://www.pbs.org/wnet/nature/episodes/my-life-as-a-turkey/wild-turkey-fact-sheet/7299/ What’s with all the ornamentation?

10. It’s all about getting a lady…

11. Lets make a turkey call… Materials: Paper cup Pencil String Scissors Paper clip Water

12. What’s happening? As your fingers move down the string they cause friction The friction causes vibrations These vibrations travel up the string to the cup The cup amplifies the vibrations, producing the sound you hear

13. How do turkeys gobble? ….she needs to hear you It happens in the syrinx (equivalent to the human vocal cords)

14. How does it work? The syrinx is a boxlike organ with elastic vibrating membranes – Similar to the rubber bands we played with As air is exhaled from the lungs it crosses through the boxlike syrinx and is amplified – Similar to how sound was amplified inside our turkey call cup

15. How do they make different sounds? There are muscles attached to either side of the syrinx – These muscles are used to add tension to the membranes – Remember what happens when we changed the tension on the rubber band? The pitch is altered The turkey can make the sound louder or softer by increasing or decreasing the air flow through the syrinx

16. Lets hear how it really sounds http://www.youtube.com/watch?v=5gHhHH7 pwYE http://www.youtube.com/watch?v=5gHhHH7 pwYE