25 Days of STEAM: Tornado In A Bottle
25 Days of STEAM: Day Twenty-Three
Tornado In A Bottle
This hands-on science activity is a fun way to introduce children to the basics of centripetal force. We recommend it for children 7 and up!
As with all science experiments, safety is extremely important! We always recommend wearing safety goggles. Parent supervision is required.
Supplies You’ll Need:
- A 12 oz. Empty Soda Bottle
- Dish Soap
- Safety Goggles
- Remove the wrapper from around the plastic bottle – as well as the cap. Rinse it out so that there is no residue.
- Pour a pinch or two of glitter into the bottle.
- Add a few drops of dish washing soap.
- Fill the bottle with water so that it is 2/3rds full. Place the cap back on.
- Flip the bottle upside down so that you are holding it by the neck. Move your hand in a circular motion for several minutes. Stop the movement and observe.
What is happening?
When you spin the bottle in a circular motion, you are creating an “underwater tornado” (a vortex). In a vortex, water spins real rapidly around a center point. This is due to what’s called centripetal force. A tornado is a type of vortex that exists due to the violent rotation of air around a central point. In this science activity, you can see the “tornado” through the bottle. The water and glitter represents the air.
- Centripetal Force – (n.) an inward force directing an object or fluid such as water towards the center of its circular path