A little bit of science magic. What happens when you push a skewer all the way through a balloon? It pops, right? Not necessarily.
What you need:
- balloon
- wooden skewer
- vegetable oil
What to do:
- Stretch out a balloon and then blow it up until it is quite big. Then let some air out until it is about two-thirds its original size, then tie off the balloon.
- Coat the wooden skewer in vegetable oil (be careful not to get any splinters).
- Gently push the skewer through the balloon near the tied end.
- Gently push the skewer out the other near near the top of the balloon.
What happens
The balloon won’t pop, despite having been pierced with a sharp skewer. The vegetable oil used to coat the skewer is used for lubrication, you could also use dishwashing liquid. The balloon is pierced at each end because these are the areas under the least amount of tension – that is where the balloon is stretched the least. The long chains of molecules (polymers) that make up the balloon stretch as the balloon is blown up. When you pierce the balloon, the polymers are able to stretch around the skewer, as those particular parts are not under much tension.
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