Changing the pitch of sound
🌟 This Topic is About...
- 🎵 I will investigate how to change the pitch of sounds.
- 🔮 I will make predictions and check if they are correct.
- 📊 I will describe patterns I notice in results.
- 💡 I will form conclusions using my science knowledge.
I’m ready to explore the science of sound! 🎶👩🔬
🌟 Key Words
- loosen
- tighten
- stringed instrument
- tune
- wind instrument
📖 Tap to Learn the Meanings!
- 🔄 loosen: To make something less tight or stretched, like a guitar string.
- 🔧 tighten: To pull or twist something so it becomes tighter or more stretched.
- 🎸 stringed instrument: A musical instrument that makes sound when its strings vibrate (like a guitar or violin).
- 🎵 tune: To adjust the pitch of an instrument so it sounds right.
- 🎺 wind instrument: An instrument you blow into to make sound, like a flute or trumpet.
Excellent work learning these musical sound words! 🎶👏
🎸 Stringed Instruments
Aguitar is a stringed instrument. Some strings are thicker than others. Stringed instruments have pegs that you can use to tune the instrument by making the strings looser or tighter. When the guitar is tuned, the pitch gives a perfect sound. If you listen to music and the instrument is out of tune, the music sounds unpleasant.
🎶 Changing the Pitch
You can also make the strings shorter by pressing them down. These actions change the pitch of the notes — tighter or shorter strings produce higher-pitched sounds, while looser or longer strings make lower-pitched sounds.

🎵 Have Fun with Wind Instruments
Each of these pictures shows a wind instrument. Some have one pipe and others have many pipes. People make music from wind instruments by blowing down or across the tops of hollow pipes. This makes the air vibrate inside the pipe to make a sound.
💨 Changing the Pitch
To change the pitch of sound on a wind instrument, you have to block one or more of the holes so that the column of air inside the pipe becomes shorter or longer. A shorter air column produces a higher pitch, while a longer air column makes a lower pitch.
🔍 Think like a Scientist – Make Sounds by Blowing
🧰 You will need: Eight glass bottles of the same size, water, food colouring, and a large jug.
🧪 Method:
- Line your bottles up on a table. You are going to make your own wind instrument and use it to change the pitch of the sound.
- Pour water into the jug and colour it with a few drops of food colouring. Pour water into each bottle as shown in the picture.
- Gently blow across the top of each of the bottles.
- Did you make sounds? Are the sounds from blowing across each of the bottles the same pitch?
- Predict what pitch of sounds you will make when you blow across the other bottles.
- Collect evidence to test your prediction.

❓ Questions:
“The ______________ the level of the water, the longer the column of air in the bottle and the lower the ______________ of the sound.”
🌟 Tap to See Answers
- 1: Bottles with more water have a shorter air column and make a higher pitch. Bottles with less water have a longer air column and make a lower pitch. 🎵
- 2: The lower the level of the water, the longer the column of air and the lower the pitch of the sound. 💧
Fantastic investigation! You’ve just made a wind instrument using bottles! 🎶👏
🔍 Think like a Scientist – Continued: Make Sounds by Blowing
❓ More Questions:
“The longer the column of air, the slower the vibrations and the _______________ the pitch of the sound.”
🌟 Tap to See Answers
- 3: One bottle might not fit the pattern if it had a slightly different water level or shape, which changes the air column length. ⚖️
- 4: The longer the column of air, the slower the vibrations and the lower the pitch of the sound. 🎵
- 5: We used the same size and shape of bottle to make sure the test was fair and that only the water level affected the pitch. 🧪
Excellent reasoning! You’ve learned how air vibration changes the pitch of sound! 👏🎶
💡 How am I doing?
Demonstrate to a family member how to make a sound by blowing across the top of a bottle. Show them how changing the water level changes the pitch of the sound!