Hooked on science: Tornado in a bottle

Tornadoes are considered nature's most violent storms, and you can make one at home by using a few items from around the house.

Materials

* Metal washer

* Two plastic soda bottles

* Electrical tape

* Water

* Dish detergent

Instructions

Step 1: Fill one of the plastic soda bottles half of the way with water and then add a few drops of dish detergent.

Step 2: Using the electrical tape secure the bottle openings together with the metal washer between the plastic bottles.

Step 3: Quickly turn the two plastic bottles vertically so that the bottle with the water is on top, and, holding the bottles, rotate your wrist.

Explanation

The centripetal force created by rotating the bottles in a horizontal circle pulls the water toward the center of the bottles. Gravity then pulls the water to the hole in the washer. As the water flows through the washer a vortex is formed.

Jason Lindsey is a Science Outreach Educator with Hooked on Science. Check out his website "Hooked On Science" at hookedonscience.org for webcasts and experiments that might get you hooked on science. Send him your science questions at jlindsey@hookedonscience.org. More science experiments can be found at www.semissourian.com.