In this demonstration, the students compare the elasticity of bubbles and balloons.
Bubbles seem to have a lot in common with balloons. They’re both made of a stretchy substance surrounding some air and they’re both elastic. In other words, when you stretch a balloon and a bubble and then let go, both will return to their original shape.
Blow up a balloon, then let go—the balloon goes back to its deflated form.
Start blowing a bubble, then stop—the bubble becomes a flat bubble film again. The big difference is that after a balloon is deflated it loses all its tension, but a bubble film always has its stretch no matter how small it gets.
Other things that have elasticity are rubber bands, steel coat hangers and underwear. Even human skin is elastic—it’s the loss of elasticity that causes wrinkles!
