Wind tunnel

Make your own tornado!

Difficulty:
Danger:
Duration:
15 minutes

Safety

  • Carefully review the general safety advice on the back of the box cover before starting the experiment.
  • Keep your hair away from the setup.
  • Read the "Working with Batteries" section of the safety guidelines carefully before proceeding. Always disconnect the setup after finishing the experiment.
  • Disassemble the setup after the experiment.

Step-by-step instructions

Construct a stand for a wind tunnel and its motor.

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Attach the main element—a propeller—to the wind tunnel motor.

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For the motor to spin the propeller, it must be powered by an electric current from batteries.

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A pipe placed on the propeller limits the work area of the propeller. A ring on top of the tube keeps the balls inside. Turn on the propeller and enjoy the show!

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Disposal

  • Dispose of solid waste together with household garbage.
  • Dispose of used batteries in accordance with local regulations.

Scientific description

Wind  is the air  that can drive ships across the sea, rotate the blades of wind turbines, and sometimes even tear roofs off of houses. What is it about air that can move objects?

Air is not a single entity; it consists of small parts  that can move and collide with each other and surrounding objects. When many of these parts  simultaneously move in the same direction, they can shift objects. This directional motion is called airflow . The more air parts are in it, and the faster they move, the stronger the flow.

How do you create airflow ? The movement of a solid object sets the air around it in motion, forming a flow  that spreads from the object. In the experiment, the propeller  creates a stream . The blades  spin, simultaneously twisting and pushing the surrounding air away from them. Therefore, the flow from the propeller takes the form of a spiral.The flow picks up the balls  and spirally lifts them to a certain height, where they begin to move in a circle. The farther the flow moves from the object that created it, the weaker it becomes. Therefore, the larger the ball, the closer it spins to the propeller.