Overview
Sound is by produced by the vibrations of particles that travel through the air (or another medium) and reach a person’s ear. The ear in turn then recognizes those vibrations as sound.
Science Vocabulary:
- Sound – (n.) is a vibration that travels through matter to a human’s ear to be heard.
- Air Particles – (n.) a mixture of solids and liquid droplets that pass, float or pollute the air.
Supplies Needed:
- Two Large Craft Sticks
- Straw
- Two Small Rubber Bands
- One Large Rubber Band
- Scissors
Instructions
- Take the straw and cut off two pieces about 1 inch in length. Set them aside.
- Take the large rubber band and run it lengthwise over one of the large craft sticks.
- Next, insert one piece of the small straw sections underneath the large rubber band about 1/2 inch down from one end of the craft stick.
- You will then take the second craft stick and lay it on top of the first one.
- Secure the craft sticks together by wrapping one of the small rubber bands around the end of the stick a few times, about 1/2 inch from the top. Make sure that you have wrapped it on the same side where you placed the piece of straw.
- Place the second straw section on top of the rubber band in between the two craft sticks, on the opposite end, approximately a third of the way down from the end of the sticks.
- Secure this end of the craft sticks together by wrapping the last rubber band around the end of the stick a few times, about 1/2 inch from the top.
- Once you have completed the above steps, place your lips in between the two straws (as if the sound sandwich is a harmonica) and blow. A sound should be produced. If there is no sound made, try loosening the rubber bands at the end. Also, double-check that there is one straw underneath the large rubber band and one on top of the large rubber band.
What Is Happening?
Sound is produced by the vibrations of particles that travel through the air (or another medium) and reach a person’s ear. The ear in turn then recognizes those vibrations as sound. When you blow into the “Sound Sandwich”, you make the large rubber bands vibrate which then causes the air particles around the rubber band to vibrate and then travel to your ear as sound.
It’s important to note that large objects that are long will vibrate slowly. As such, they will produce a low-pitched sound. While shorter, less massive objects vibrate quickly. This in turn produces a higher-pitched sound. You can demonstrate this concept by moving the two straw pieces closer together. When you move the straw pieces closer together, you shorten the length of the rubber band that vibrates. When you blow into the Sound Sandwich with a shortened rubber band, you will notice that the pitch of the sound is much higher.
Books about sound and music
What Are Sound Waves? Light and Sound Waves Close-up by Robin Johnson
Do You Really Want to Yell in a Cave? by Daniel Maurer
I Got Rhythm by Connie Schofield Morrison
Max Found Two Sticks by Brian Pinkney
By the Light of the Moon by Frann Preston-Gannon