What you need:
A glass bowl, plastic cling wrap, one teaspoon of raw rice, a metal pan, a metal spoon
What to do:
1. Cover the top of the bowl with the plastic cling film. Make sure the plastic is stretched taut over the bowl.
2. Put the rice grains on the stretched plastic.
3. Hold the metal pan upside down right next to the bowl. They do not need to touch, just being close to each other is enough.
4. Now, the fun part: Start banging the pan with the metal spoon.
What happens?
Even though the bowl and the pan aren’t touching, the rice grains on the plastic begin to dance around. If you observe it carefully, you’ll see that the rice keeps time with your spoon-beating!
Why?
Sound usually travels in the form of waves. The sound of the clanging metal travels towards the bowl and hits the plastic film. This makes the thin film vibrate and the rice grains start to bounce. Their bobbing is in time to the sound waves hitting the film!
In a similar manner, sound also travels to our eardrum and we experience its vibrations. That’s how we hear.
Picture Credit : Google
