Popping balloons

[creampuff]

The pop when a balloon balloon bursts:
Is it a sound wave travelling at the speed of sound?
Is it a shock wave which is supersonic?

[TwigtheWonderkid]

It's just a shock wave, of the air that was contained under high pressure escaping rapidly. If you need to pop balloons and don't want the bang, put some sellotape on the balloon and stick the pin thru the tape. The tape stops the balloon ripping so the air can't escape quickly, so it just comes out quietly and slowly.

[Beati Dogu]

I think the air pressure change is minor, it'll only be about 1 PSI above atmospheric pressure before it can't stretch any more.

The noise is from the sudden release of energy in the elastic balloon material. As I understand it, this shockwave is supersonic in the latex, which is near the speed of sound in air. The sound will bounce around the room, magnifying it. Pop one without any reflected sound and it's not that dramatic:

https://www.youtube.com/watch?v=MyP7i1B_QNk


I've done that trick with sellotape and a balloon before. You can stick a knitting needle right through it, as the sellotape stops the tear propagation.

[annodomini2]

TwigtheWonderkid said:

It's just a shock wave, of the air that was contained under high pressure escaping rapidly. If you need to pop balloons and don't want the bang, put some sellotape on the balloon and stick the pin thru the tape. The tape stops the balloon ripping so the air can't escape quickly, so it just comes out quietly and slowly.

Don't bother with tape, pair of scissors, pinch the neck of the balloon so the piece of the balloon material you are going to cut is slack and not under pressure. Make a small cut 5-10mm long and release the pinch on the neck and it will deflate rather than pop.