Fluids > Fluid Statics > Atmospheric Pressure
DCS# 2B30.70

VACUUM BAZOOKA

 

APPARATUS
vacuum bazooka
202-alcove
mylar
202-16-F6
pvc coupler
202-16-F6
fresh ping pong ball
202-16-F6
vacuum pump
202-cart
exacto knife
202-02-E2
ear plugs
013B-02-B
can holder
202-16-F6
three pop cans

 
DESCRIPTION
The bazooka is loaded with one or more ping pong balls and its ends sealed with mylar.  Evacuate the tube, then puncture the mylar at the ping pong ball end and the inrushing air will drive the ball with great speed out the other end, through two or three pop cans in its path.

NOTES

Prepare the bazooka by loading the ping pong ball and sealing each end with a square of mylar held in place with a rubber coupler and hose clamp.

Mount it at a slight angle so the ball stays near the puncture end.

A pair of photogates can be used to determine the exit speed of the ball.  Measurements using the 3-m version yield speeds of about 250 m/s.


REFERENCE
TPT 41, 246-247 (2003).

Am. J. Phys., Vol. 72, No. 7, July 2004