Sounds like a Turkey

Happy Thanksgiving!!!-I am thankful for

wonderful students

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

What makes the different pitches

• The wavelength of each sound wave determines the pitch

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?

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

Review: Thin versus thick string

• Thin = High• Thick = Low

http://pbskidsorg/designsquad/games/string_thing/msg_how_sound_works.swf

Review: Less versus more tension

http://pbskidsorg/designsquad/games/string_thing/msg_how_sound_works.swf

• Less tension = High• More tension = Low

Why do they look and sound so ridiculous?

Brad Allen

http://www.pbs.org/wnet/nature/episodes/my-life-as-a-turkey/wild-turkey-fact-sheet/7299/

What’s with all the ornamentation?

It’s all about getting a lady…

Lets make a turkey call…

Materials:• Paper cup• Pencil• String• Scissors• Paper clip• Water

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

How do turkeys gobble?….she needs to hear you

It happens in the syrinx(equivalent to the human

vocal cords)

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

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

Lets hear how it really sounds

• http://www.youtube.com/watch?v=5gHhHH7pwYE