DEMONSTRATION #3 - Flying Ping-Pong Ball
Supplies:
Hand held hair dryer, or vacuum cleaner with blower function
and hose
Ping-Pong balls (1 or more)
Procedure:
Turn on the dryer or vacuum cleaner and hold it so the air
blows straight up. Drop a Ping-Pong ball onto the center of the
stream of air. A low power stream of air will work better than a
more powerful stream. The ball will dance around suspended in the
air. With practice, you can move it around the room without having
it fall down. Try the same thing with a 1" by 6" strip of paper.
Hold the paper just below the stream of air.
Explanation:
The stream of air going over the curved surface produces an area of
lower pressure, pulling the object in the direction of the lower
pressure. This is part of what is known as Bernoulli's Principle
and is part of the explanation of how airplane wings get their lift.
Since the ball is round, not wing shaped, the pressure is all around
so the ball stands approximately still. With the paper, lift is
actually created and demonstrated.
Last modified: Thu Nov 7 14:50:35 PST 1996