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The Bernouilli Effect
You will need:
- a hairdrier
- a tube wider than the ball
- a ping pong ball or other light plastic ball
What to do:
Switch the hairdrier on with the air flowing upwards. Balance the ball
in the airflow. Try moving the hairdrier around band tilting it. The gravity
force pulling the ball down is balanced by the pressure difference due to
the speed of the air moving around the ball - Bernoulli's principle.
Now place the tube vertically over the ball - what happens?
The ball should be rapidly sucked up the tube, as the fast air moving up
the tube creates low pressure in the tube.