developed by W.K. Adams

Students experiment with various sound sources, including straw instruments and water bottles, to gain an understanding of the connection between sound and vibration. This lesson is designed for uses AFTER the Sound and Music introductory lesson.

Science Topics

Sound
Vibrations
Resonance
Comparing Frequency

Process Skills

Observing
Scientific inquiry
Predicting

Grade Level

6-12

Set-Up

5 minutes

Activity

35-45 minutes

Clean-Up

5 minutes

Learning Goals

Students will be able to:

  • describe how sounds are produced with vibrations
  • describe how tones can be varied by changing the length of a resonant cavity
  • list some of the instruments found in the woodwind, brass, and string families

Materials in Kit

Straw instrument*

Materials not in Kit

Water bottle – 1 per group
Water (to add to bottles)**
Scissors – 1 per group

Optional Materials

Extra Straws – 1 per student
Computer***
Extra water bottles

*Students can use the straw instrument they built for the introductory Music and Sound lesson, or you can gather materials to make new ones.
**You will want a source to refill the water bottles (sink, extra containers of water, etc.)
***You might want to access http://www.dsokidts.com (see extensions below)

 

Advanced Preparation

Complete the Sound and Music introductory lesson before this activity.

Set-Up

Gather materials and arrange them so they can be easily distributed to students during class.

Introduce the Activity

Begin with a short pre-assessment, where students complete three questions making predictions about the upcoming activity. Students will answer questions 1-3 in their worksheets. After the students have answered 1-3, they should discuss their answers in small groups before moving on.

Doing the Activity: more with straw instruments

  1. Students will need to use their straw instruments from the Sound and Music lesson to create sounds.If you need to create new straw instruments, review the directions below and read the instructions from the Sound and Music lesson
    • Model the building of the instrument for the class and explain safety procedures to the students
    • Cut the tip of the straws into a point
    • Gently chew on the straw to soften the tip
    • Blow really hard into the pointy end to create a sound
  2. With their straw instruments, students should answer questions 4-5.
  3. For questions 6 and 7, students will need to modify their straw instruments by removing the white straw. They will then cut a small a 1-inch section off the red straw and blow on it, and note how the pitch has changed. They will continue to cut their straws down, writing down how much the pitch changes with each change in length. They should cut the straws down until there is nothing left to use. NOTE: If you have extra straws, students can create new straw instruments instead of cutting their straw trombones.
  4. Question 8 expects the students to have heard about resonance previously. If they did the Sound and Music lesson, they will have heard a definition before in the pasta/raisin demonstration.

Doing the Activity: water bottles

  1. For question 9 and 10, one student should blow over the top of the water bottle until he or she makes a tone.
  2. To figure out where the resonance is happening and to answer questions 12-13, students should try to make a new tone by add or removing water.

NOTE: Make sure students take turns blowing over the top of the water bottle!

Explanation

  • The straw instruments create sound when the reed (cut tip of the straw) vibrates. The cavity in the straw allows the vibrations in the air to resonate. This not only defines the pitch of the straw but also makes it loud.
  • The water bottle makes a higher tone the more water is in it. This is the same general principle as the straw instrument. The sound waves resonate in the air space of the bottle.

Key Lesson Terminology

Resonance – A natural frequency of vibration determined by the size and shape of an object

Pitch – how low or high a town sounds to a person

Tone – a musical sound of specific frequency or pitch

Vibrations (oscillations) – a shaking back and forth movement

Optional Extensions

  • For question 13, students can go to the website www.dsokids.com and go to Listen By Instrument to help determine what kind of instrument the straw instrument and water bottle can be classified as.
  • Students can create a vocabulary sheet to keep track of the terms used in the lesson.
  • Students who play a woodwind instrument can bring their instruments to lass to show how the learning translates to real life.
  • Complete the Musical Instruments Part 2 lesson