Something has to shake
Press a ruler on a desk edge, with one end hanging out. Flick that end with a finger. It buzzes. Hold it still, and the buzz stops. The buzz is a to-and-fro movement. We call it a shake, or a vibration.
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Step 1 of 4
- At rest, the source is still.
- It swings out one way.
- Then back the other way — one shake.
- Held still, there is nothing to shake.
Rule
Every sound is made by something that vibrates. Stop the vibration and the sound stops.
- Vibration — a to-and-fro movement, again and again.
- Source — the object that makes the sound.
Sources shake in different parts:
- A stretched string, as in a veena.
- A stretched skin, as in a drum.
- The air inside a pipe, as in a bansuri.
- Vocal cords, in your throat.
Tap a steel bowl. Rest a finger on its rim. You feel it buzz. Grip the rim and the ring stops. The bowl can no longer shake.