PURPOSE: To demonstrate the Venturi effect in a dramatic way.

DESCRIPTION: In this Venturi tube the levitation of the ping pong balls in an airstream is used as a pressure sensor; the higher the ball the greater the pressure of the air coming from that hole. Both the venturi effect and the reduction of pressure along the tube can be seen.

Note that the reason that the balls are levitated in the vertical airstream is NOT the Bernoulli effect, but rather the Coanda effect. Refer to demonstrations F5-01, F5-02, and F5-06 for a detailed explanation.

SUGGESTIONS:

REFERENCES: (PIRA 2C20.26) See Demonstration Reference File for further information.

EQUIPMENT: Venturi tube, ping pong balls, blower.

SETUP TIME: None.