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Q & A: What is a sound

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Most recent answer: 10/22/2007
What is sound?
- E. L. De Santiago
E. S. School, San Francisco,CA
To understand what a sound it, just put your hand on your throat and start talking. What do you feel? Hopefully your hand will feel that your throat is vibrating at exactly the same time as sounds are coming out of your mouth. This tells you that vibrations in your throat cause the sounds you make. (The parts of your throat that vibrate are called your vocal chords).

The vibrations of your vocal chords cause the air in your throat to vibrate back and forth as well, this causes the air in your mouth to vibrate, which causes the air in front of your face to vibrate and so on. Sound, then, is just vibrating air. The quicker the vibrations the higher the note you make (try humming high and low notes while holding your throat again to see what I mean...can you feel any difference?).

You hear sounds when the vibrating air causes a small membrane in your ear to vibrate (called your eardrum).

What if there was no air? Well, then you would not hear any sound since there is nothing to transfer the vibrations from their source to your ear.


(published on 10/22/2007)

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