Why are some sounds high and some sounds low?
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Why are some sounds high and some sounds low?
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DISCUSS:

What do you think--what makes one sound LOWER and another HIGHER?

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Get a copy of this worksheet and fill in the two questions you just discussed. (You’ll answer the other questions later.)

High vs low pitch

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DISCUSS: How would you describe the differences between the high-pitched and the low-pitched sound wave?

High vs low pitch

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Circle which words you'd use to describe the high-pitched wave versus the low-pitched wave:

Worksheet spread out vs scrunched

Note: Be sure to play with the online oscilloscope we link to in the Extras!

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DISCUSS:

Which of these is the HIGHEST pitch? Explain how you know.

Oscilloscope images

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DISCUSS:

Which of these is the LOWEST pitch? Explain how you know.

Oscilloscope images

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Optional Extras

Below are ideas for extending this topic beyond the activity & exploration you just completed.
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Reading

“Now Hear This!” describes the invention of a sound maker designed to repel kids & discusses sound waves. This Common Core-aligned reading is free with registration on ReadWorks. It includes comprehension questions to be downloaded separately.

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Online Tool: Bouncing Balls

Can you be so quiet that that this online sound detector doesn't even know you're here?

When you open this online tool, choose "Begin Bouncing" and then click on the picture of a microphone. A screenful of balls will bounce whenever your computer's microphone detects a sound. Start by clicking here.,

For an extra challenge, select “emoji” and set bounciness to the max. Now try to keep those balls from bouncing!

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Hearing Test

Use this online test to find the highest and lowest pitch you can hear.

  • The video starts with a tone so low you probably can't hear it. Keep listening.
  • When you do you start hearing the hum? Notice when it gets so high you can't hear it anymore.
  • While you're listening, watch the waves. They change with the pitch — from long wavelengths to short.
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Oscilloscope Experiments

You can continue exploring sound waves with the web-browser oscilloscope on the next slide. It only works in Chrome or Firefox, which you can download for free here: download Chrome or download Firefox.

Here are 3 experiments to try with the oscilloscope:

  1. Sounds that are a mix of pitches make messy waves. Can you find a sound that makes a simple wave? (Try whistling.)
  2. What happens to the oscilloscope picture when you make a sound louder or softer?
  3. What happens when you make a sound higher or lower?
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Oscilloscope

Get ready to see sound. This oscilloscope only works in Chrome and Firefox and it requires a microphone on your computer.

When you click this button your browser will ask you permission to use the microphone.

Look at the top of your screen ☝️

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Video: Singing Roads

The pitch of a sound — how high or low it is — depends on the vibration that made the sound. The quicker the vibration goes back and forth, the higher the sound.

On this singing road, the vibrations of a car play a tune. Bumps in the road called rumble strips make the car vibrate.

Play the video, then discuss: Which set of rumble strips plays the higher note? Close together and far apart rumble strips

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Image & Video Credits

Mystery Science respects the intellectual property rights of the owners of visual assets. We make every effort to use images and videos under appropriate licenses from the owner or by reaching out to the owner to get explicit permission. If you are the owner of a visual and believe we are using it without permission, please contact us—we will reply promptly and make things right.

Exploration
Relaxing 3 Hour Video of California Ocean Waves by MoneySavingVideos , used under CC BY
three girls laughing and walking by Mat Hayward
girl singing karaoke by Elnur
"the mosquito" by LadyofHats , used under CC BY
17400 Hz 17.4 kHz Sine Wave Sound Frequency Tone Mosquito Tone by Beeps, Chirps and Noise/EpicPuzl781
speaker system by MeemiePhoto
7 Eleven Fukushima Shinchi Town Shop by Kuha455405 , used under CC BY-SA
assembling circuit components by Robert Wydro Studio
black speaker by gualtiero boffi
girl covering her ears by Dean Drobot
hands holding cell phone by Africa Studio
students sitting in class by Rawpixel.com
girl playing flute by aboikis
man playing tuba by Ollyy
man playing flute by charles wong , used under CC BY
young boy playing tuba by jaishaunglover11
man playing guitar isolated on black background by Pressmaster
Schlieren by NASA , used under Public Domain
schlieren effects: book close by Mike Hargather
schlieren effects: audio/sound by Mike Hargather
schlieren effects: bottle rocket by Mike Hargather
ripples in a pond by IRIS EPO
visual: schlieren effects by Mike Hargather
oscilloscope by rwg42985
oscilloscope generator by Academo , used under Public Domain
Other
trombone player by Ollyy
Overview
Grade 4th
Topic Sound, Waves, & Communication
Focus Sound, Vibrations & Waves
Print
Activity Prep

In this Mystery, students discover that sound is a wave. In the activity, Making Waves, students draw the waves that different sounds make using a virtual oscilloscope, a machine that shows images of sound waves. Then they vibrate a rope to make waves that look like the ones made by the oscilloscope.

Preview activity

Number of students:
Clotheslines
Cut to 12-15 foot lengths. Jump ropes or telephone cords will also work.
Details
60 feet
Be The Vibration printout Print 30 copies
Be The Vibration Answer Key printout Print 1 copy
Sound Vibrations printout Print 30 copies
Sound Vibrations Answer Key printout Print 1 copy
Prep Instructions

For the rope activity, you’ll need a smooth, hard floor where you can stretch out a rope that’s 12 to 15 feet long. Students can take turns making waves. We suggest having at least one rope for each group of 8 students.

Prepare the Rope or Clothesline

For each group of students, you’ll need a flexible rope or clothesline measuring 12 to 15 feet in length.

Virtual Oscilloscope Extension (Optional)

In our Extras section, we include a link to an online oscilloscope that you can use to extend your exploration of the patterns made by sound. Using this tool, students can experiment with different sounds and see the patterns that the waves make.

Overview
Grade 4th
Topic Sound, Waves, & Communication
Focus Sound, Vibrations & Waves
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