Book 4, Question 105 · Video
Why Do Water Striders Walk on Water?
A pond has a thin skin called surface tension! A water strider is light, and its long legs spread out its weight. Its hairy feet make little dimples in the skin, instead of punchin
Read the full answer →What Crafty Clover says in this video
Intro
Hey there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why do water striders walk on water?
The Big Idea
A pond has a thin skin called surface tension! A water strider is light, and its long legs spread out its weight. Its hairy feet make little dimples in the skin, instead of punching through. It's like standing on a tiny trampoline.
Water Has a Skin
Step one: water has a skin. At the surface, water molecules cling to each other. That makes a thin, stretchy skin called surface tension. You can even see it when a drop rounds up.
Light Body, Long Legs
Step two: a light body, and long legs that spread out. A water strider is very light, and its long legs spread its weight over a big area. That way, no one spot pushes hard. Less weight on each spot means it doesn't break the skin.
Hairy Feet Dimple, Push and Glide
Step three: hairy feet dimple, and the strider pushes and glides. Tiny hairs on the feet push down on the water and make little dimples. The dimples act like tiny trampolines, so the insect can push against them and glide. Zoom, zoom, across the pond!
A Closer Look
Let's take a closer look at surface tension! The water skin stretches at the surface. A hairy foot makes a dimple in the skin. And the long legs and light body keep the strider on top.
Quick Facts
Quick facts! A drop of soap can wreck that skin. That is why soap in a pond is a problem. Some spiders can do a short surface dash too. Other light insects use surface tension too. Watch water striders from the edge, and keep your feet dry.
Think Like a Scientist
Now, think like a scientist! With a grown-up, gently lay a clean paper clip on still water. What held the paper clip up? Then add a drop of soap. What changed? Watch a water strider's dimples from the bank.
Outro
A skin of water and a few clever legs make walking on water possible! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!