December 18, 2020

Get an up-close look at how a tornado works by creating one using two plastic bottles

Tornado Watch

Tornadoes are huge and powerful forces of nature that can happen anywhere around the world. They occur when a thunderstorm is formed and the high altitude combined the with change in wind direction causes the wind to swirl. Warm air is sucked up from the ground and it forms a funnel cloud. The funnel begins to get large and stretch toward the ground. When it touches the ground, it is a tornado.

With this quick and simple activity, you can get an up-close look at how a tornado works by creating one using two plastic bottles. We will create our tornado by spinning water inside a bottle and then quickly changing the pressure in the bottle. The pressure changes because the water is trying to quickly go through the neck of one bottle to the neck of the other.

This activity is best suited for students in elementary school grades. It includes about five minutes of preparation time and about 15 minutes of activity and learning time.

Materials:

  • 2 two-liter bottles
  • Duct tape
  • Water

Directions:

  1. Fill one of the two-liter bottles about halfway with water.
  2. Place the other two-liter bottle opening to opening.
  1. Use the duct tape to seal the openings together
  2. Keeping the bottle vertical, hold the bottles by the duct tape and swirl the water in a clockwise rotation.
  3. After you rotate the water a few times turn the bottles over.
  4. Rotate once the opposite direction.
  5. Observe the tornado.

Add a little more fun to the learning by throwing in some glitter or other objects to watch them move through the tornado. You can also encourage learners to come up with other ways of sealing the bottles together to see if they can change the size of the tornado.