Create a water vortex in a bottle. The water is rapidly spinning around the center of the vortex due to centripetal force. This is an inward force directing an object or fluid such as water towards the center of its circular path. By the way, vortices found in nature include tornadoes, hurricanes, and waterspouts.
Fill the plastic bottle with water until it reaches around three quarters full.
Add a few drops of dish soap.
Sprinkle in a few pinches of glitter (this will make your tornado easier to see).
Put the cap on tightly.
Turn the bottle upside down and hold it by the neck. Quickly spin the bottle in a circular motion for a few seconds. Stop and look inside to see if you can see a mini tornado forming in the water. You might need to try it a few times before you get it working properly.