ALTOONA, Pa. (WTAJ) — In this episode of Science with Shields, Christy Shields shows you how capillary action works by making a toothpick star.
What you need:
- Toothpicks (preferably made out of birch)
You will need 5 toothpicks for this experiment. Take each toothpick and bend it in half with breaking it, but not breaking it the whole way in half. The tooth pick should still be attached together. Arrange the toothpicks on your plate in a small star shape. Using the pipet, put water into the middle of your star and watch it grow!
The star expands when you add water onto it. This happens because you have dry wood from the toothpick, and when it gets wet from the added water, it grows larger. It expands because the wood has hollow tubes in it or capillaries. These tubes fill with water and expand the star out. Plants use capillary action to grow. The plants take water from the ground into these tubes and can bring water up into all of their leaves and branches helping it get the nutrients and water that is needed for it to grow.
I found the bamboo toothpicks do not work as well as the birch ones. Try it out with different kinds of toothpicks and let us know how it goes!