Book 1, Question 110 · Video
Why Does Rubber Stretch? Tangled Chains That Snap Back!
Rubber is made of long, tangled molecule chains. When you pull, the chains unkink and straighten out, and when you let go they snap back into a tangle. The page says pulling too mu
Read the full answer →What Crafty Clover says in this video
Intro
Hi! I'm Crafty Clover! Let's discover something amazing. Why does rubber stretch?
The Big Idea
Pull a rubber band, and it stretches way out. Let go, and snap! It zips right back. How? Rubber is made of super long, tangled chains, too tiny to see. They can straighten out, and curl back up! Let's see how it works, step by step!
Rubber Is Long Tangled Molecule Chains
Step one: rubber is made of long, tangled molecule chains. Each chain has thousands of tiny pieces linked together, all twisted up like a bowl of spaghetti. The chains are also tied to each other in a few spots, so they can't slide apart.
Pulling Unkinks the Chains
Step two: pulling unkinks the chains. When you stretch rubber, the twisty chains start to straighten out, and line up. That's why a rubber band can stretch several times longer than it started!
Let Go and the Chains Snap Back
Step three: let go, and the chains snap back. The tiny chains are always jiggling and wiggling, and that wiggling pulls them back into a tangle. The tie spots guide each chain back into place. Snap! The band is back to its old shape.
Rubber Band Close-Up
Let's zoom way in on a rubber band! Inside, the chains loop and tangle all around each other. In a few places, the chains are linked together, like a net. Stretch, and they straighten. Let go, and they curl right back!
Quick Facts
Quick facts! Too much pull, and the chains break. Snap! The band tears apart. Natural rubber comes from a milky sap, from rubber trees. Cold rubber gets stiff, and warm rubber is stretchier. And tires, balloons, and erasers are all made with rubber!
Think Like a Scientist
Now, think like a scientist! Stretch a rubber band slowly, then let it rest. Does it go back to the exact same size? Now stretch it many times. Does it change? Measure it with a ruler, before and after! Write down what you notice.
Outro
Rubber stretches because its long tangled chains straighten when you pull, and snap back when you let go. Keep stretching your brain! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!