how do instruments like violins & cellos make their sound with a bow run across their strings?

[U-Dub/BYU fan♂]

[Best Not Broken]

Someone will almost certainly explain this better than I can, but here goes anyway.

When you tune the string, you're adjusting the pitch at which it will resonate once it is plucked, strummed, or bowed. The bow, which has resin on it to increase the friction, rubs against the string, causing it to vibrate at the frequency to which you tuned it.

The body of the bass/cello/violin acts as an amplifier--the wood resonates with the vibration of the strings, and the size of the instrument's body more or less detemines how much volume you'll get from the instrument.

Think about when you dip your finger and rub it gently around the rim of a crystal glass--you can almost feel the vibration in your fingertip, and the large open area of the glass acts as a primitive amplifier. Add water to the inside of the glass and you change the pitch at which it vibrates. It's a very similar concept.

I hope that makes some sense!

-Nik
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