What does a tornado look like up close? A tornado is a spinning column of air called a vortex. You can create a water version of that same spinning motion using two plastic bottles.
You drill a hole in the center of two bottle caps. Seal them together with silicon caulking and wrap the outside with duct tape. Fill one bottle about three-quarters full of water. Screw both bottles onto the joined caps.
Flip the bottles upside down and swirl them in a few quick circles. A spinning funnel of water forms as the liquid drains from the top bottle to the bottom. Add food coloring or plastic confetti to see the vortex more clearly.
Hypothesis
The hypothesis is that a vortex will form when the two pop bottles are connected and the water is drained from one bottle to the other.
When you flip the connected bottles and swirl them, a spinning funnel of water forms as the liquid drains from the top bottle to the bottom. That funnel shape is a vortex — a spinning flow of water you can watch in action. Adding food coloring or plastic confetti makes the swirling motion easier to see.
A tornado is a spinning column of air — a vortex — that pulls into a funnel shape as it reaches from cloud to ground. When you swirl two connected bottles, water drains in that same spinning motion. Add food coloring or plastic confetti and the vortex becomes visible, letting you study how the spinning funnel behaves as it forms.
Method & Materials
You will need to drill a hole in the caps of two pop bottles, seal the caps together with silicon caulking, and attach the two bottles together with duct tape. Then fill one bottle with water and attach it to the other bottle. Finally, swirl the bottles in a few quick circles to create a vortex.
You will need two 2-litre pop bottles with caps, duct tape, silicon caulking, water, a drill, food colouring, and plastic confetti.
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After completing the experiment, you will have created a powerful vortex like a tornado in your own home! This experiment is a great way to learn about the power of tornadoes and the science behind them.
Why do this project?
This science project is so interesting and unique because it allows you to create a powerful vortex like a tornado in your own home.
Also Consider
Experiment variations to consider include adding food colouring or plastic confetti to the water, or using a “Tornado Tube” adapter to connect the two pop bottles without drilling or gluing.
Full project details
Additional information and source material for this project are available below.
