Sound Exploration will go here.

link to asu
What makes sound? Vibration
-- Sound is caused by air molecules moving back and forth. This is called a vibration.
  • High pitch, loud sounds are created from frequent hard vibrations.
  • Low pitch, loud sounds are created from less frequent hard vibrations.
  • High pitch, quiet sounds are created from frequent soft vibrations.
  • Low pitch, quiet sounds are created from less frequent soft vibrations.
How can sound be changed? By having more or less frequent vibrations.

Characteristics of Sound:
Frequency - How many compressions pass by a given spot in one second.
Pitch - Human perception of sound frequency.
Amplitude - How compressed each compression is (or how "stretched out" each rarefraction is).
Loudness - Human perception of sound amplitude.

For a fun way for students to remember these relationships, sing this song.
"This Sound Is Your Sound" (Sing to the tune of "This Land Is Your Land")
This sound is your sound, this sound is my sound!
From the hard loud whappings to the soft quiet whappings.
From the frequent high whappings to the not frequent low whappings.
This sound was made for you and me!


Music and Rubberband Activity:
This activity helps students understand a variety of ways one can produce sound.
Materials -- Cup and Rubberband
Hand each student one cup and one rubberband. Ask the students how can you make sound/music with a cup and a rubberband? Have the students experiment with the cup and the rubberband. Afterwards, place the students in a circle. The students must individually demonstrate their sound. However, each student must present a different way/technique to produce sound. For example, if Student A scratches the cup for a sound, then the rest of the students must eliminate this option.

Sound Vibrations Activity
Tie two strings to an oven rack. Leave a loop at the end of each string and place the two string loops on two index fingers. Hold the oven rack and string in your ear and ask a partner to tap the oven rack. What do you hear? Now switch with your partner. Why was the sound louder when you held the string up to your ears?
(Sound is caused by vibrations. Those vibrations cause air molecules to move back and forth until they reach the eardrum. The vibrations travel through the string and cause the sound to be amplified.)

slinkie.jpgSound and Slinkies
Slinkies can be used to demonstrate sound travel and the difference in high pitch and low pitch.
-Stretch the slinkie all the way out in a straight line on the floor.
-Hold one end of the slinkie, and pull it back and move it forward to create a ripple effect that travels across slinkie to the other end.
-This demonstrates sound travel. As sound bumps into other molecules around it, it pushes the sound along, and losses a little of it's energy with each bump. This is why things to not sound as loud from far away from the source, and doesn't continue on forever.

-Now, instead of just creating one ripple, create several evenly spaced ripples to keep the sound going. By moving quickly, sending a lot of ripples down the slinkie at one time, the demonstration is a high pitch because these sounds are high frequency vibrations. By moving slowly, sending only a few ripples down at a time, this is a demonstration of a lower pitch sound, because of the lower frequency in vibration.