Vortex cannon

An invisible bullet!

Difficulty:
Danger:
Duration:
5 minutes

Safety

  • Carefully review the general safety advice on the back of the box cover before starting the experiment.
  • Keep flammable materials and hair away from the setup.
  • Keep a bowl of water nearby when working with fire.
  • Do not leave the candle lit after finishing the experiment; this is a fire hazard.

Step-by-step instructions

Create a special muzzle for the vortex cannon!

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The elastic wall of the balloon pushes the air projectiles out of the cannon.

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The target will be a burning candle! Load the cannon and pull the trigger. Did you hit the target?

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Disposal

  • Dispose of solid waste together with household garbage.

Scientific description

The propeller  continuously pushes the air  and creates a stream . In the cannon, the air is pushed out by the release of the latex membrane. As a result, a rapid airflow  forms inside the tube  directed towards the outlet. Since the hole  is narrower than the tube itself, the airflow  is forced to accelerate as it passes through.

Escaping from the tube , the central airflow only collides with the stationary air  located in front of the exit. The surrounding airflow interacts both with the walls inside the tube, and with the outside air. Therefore, the surrounding airflow moves more slowly than its center.

The surrounding airflow is simultaneously held back by the stationary air  and pushed by the rapid central airflow. As a result, the airflow  begins to roll up like a scroll . It forms the shape of a donut  that flies forward. The outside air gently slows down the air donut , which itself consists of spinning air. In other words, the air donut gently shifts the outside air from its path, without colliding with it. Such a donut  retains its speed longer and can travel a far greater distance than direct airflow .