Invincible balloon

Place your bets – will it burst or not?

Safe­ty pre­cau­tions

Warn­ing! Only un­der adult su­per­vi­sion.


  • sharp bam­boo skew­er;
  • bal­loon.

Step-by-step in­struc­tions

In­flate a bal­loon and pierce it near the knot with a sharp bam­boo skew­er – it doesn’t burst!

Process de­scrip­tion

Since the rub­ber that the bal­loon con­sists of is elas­tic, it can be stretched tremen­dous­ly. When the bal­loon is pierced in places of high ten­sion, an in­ho­mo­gene­ity ap­pears on its sur­face, caus­ing it to burst. In oth­er words, when the bal­loon is in­flat­ed, each point on its sur­face is pulled in all di­rec­tions; the ten­sion that aris­es at the punc­ture site pulls the rub­ber apart from the punc­ture point. The air in­side the bal­loon also af­fects the na­ture of the "ex­plo­sion."

But there’s a cheat! The bal­loon won’t burst if you pierce it in the places of the least ten­sion – at the knot and at the very tip of the bal­loon. The rub­ber tight­ly fits the bam­boo stick, pre­vent­ing the bal­loon from de­flat­ing quick­ly.

Have even more fun with a MEL Physics sub­scrip­tion!