Place your bets – will it burst or not?
Warning! Only under adult supervision.
- sharp bamboo skewer;
Inflate a balloon and pierce it near the knot with a sharp bamboo skewer – it doesn’t burst!
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.
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