By Priyanka Singh
Thank you, Amodini, for such an interesting question!
When we inflate a balloon, the molecules of the material that the balloon is made of (rubber) experience a lot of tension. Every point on its surface gets stretched uniformly in all sides with high pressure air inside.
However, if we prick a hole in the surface of the rubber, it relieves the tension on the surface, as the balloon is no longer being pulled uniformly from all its sides. This causes the rubber to pull away from the hole, increasing the size of the hole in the process and the balloon bursts with a popping sound.
The high-pressure air that was inside the balloon is now free to expand and this creates a pressure wave that we hear as a popping sound or a loud bang.
