Question

what is the reason behind the sound when we fill a bottle ??​

Answer 1

Explanation:

When you blow into the bottle, you are making the air vibrate, not the glass. An empty bottle produces a lower pitch because there's lots of air in the bottle to vibrate. Adding water to the bottle decreases the amount of air space, which means there is less air to vibrate.

Answer 2

Answer:

when you fill a bottle there is air present hence decrease in air volume and increase in water makes sounds