STEM Ninth-Twelth Grade Experiments

Dow would like to thank the Chemical Educational Foundation® (CEF) for permission to use these materials. Dow is a Diamond sponsor of all CEF’s You Be The Chemist® programs. For more fun ways to incorporate science into everyday life, head to the Chemical Education Foundation’s Activity Guide

Learn more about science by exploring these experiments:


WET OR DRY MAGIC FORK EXPERIMENT

Take a drinking glass filled with water and a clean fork. Dunk the end of the fork into the water. You can control whether the water drips off when you pull it out slowly, by the angle, or by how fast you pull it out. It takes some practice, but when you pull it out slowly and straight up, the fork comes out dry and will not drip water.

If you pull it out fast and at an angle, it will drip lots of water. With practice, you can amaze your friends by altering your lifting techniques just at the water surface.

Scientific Principle at Work

Hydrodynamic flow is governed by rheological (the science of flow) properties. This is just a fancy way of saying that liquids move a certain way according to the laws of gravity and physics. The viscosity and thickness of the water-film control how fast it flows off the ends of the fork.

Note: If you're under the age of 18, be sure your parent or guardian knows what you are doing. Some of these experiments require the use of simple household tools, such as scissors and knives, and some could make a mess. Ask your parent or another adult to help.


SPINNING YO-YO EXPERIMENT

Get a toy yo-yo and practice using it. Use a piece of clear tape to attach a piece of gum centered on the side. Leave the gum in the wrapper. Now use the yo-yo as you normally would. The gum will come shooting out of the wrapper.

Scientific Principle at Work
The spinning yo-yo, like any spinning object, creates a force on each part of it equal to mass times radius times the square of the rotation rate. In other words, the faster the yo-yo spins, the larger the force it creates. So the harder you throw the yo-yo, the further the gum will fly.


Note: If you’re under the age of 18, be sure your parent or guardian knows what you are doing. Some of these experiments require the use of simple household tools, such as scissors and knives, and some could make a mess. Ask your parent or another adult to help.