Hey, sound is important in our world of communication! The highness or lowness of a sound is called the "pitch." Pitch depends on vibrations. The more vibrations the higher pitch. To learn more about pitch, try this cool sound experiment!
You will need:
Five glass bottles (same size and shape)
Water
Food coloring
A wooden spoon or stick
Here's what you do:
1. Line up the bottles in a row.
2. Leave the first bottle empty and fill each bottle with small amounts,
increasing with each bottle.
3. Add a drop of different food coloring to each bottle.
4. Tap each bottle and note the different pitches of sound. You can also
blow across the top of the bottle.
Then ask yourself:
Which bottle produces the lowest sound?
What is the relationship between the amount of air and liquid in a bottle and
the pitch that it makes?
The Answer:
When you hit or blow on the bottles you create a vibration. Sound travels through the air. Small spaces give sound waves less room and the air vibrates faster than in a large space where the air has to travel farther. Thus the bottle with no water makes the lowest sound. The bottle with the most water has very little air space, thus making a high pitched sound.
One reason we communicate is to praise God. So take time with this experiment to give sound praise to Him. Play a song on your glasses in praise to God. In fact, get a bunch of friends together and have a full orchestra!
Try other experiments!
Tornado in a Bottle
Carbon Dioxide Balloon
Sound and Pitch
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