Sponsored by Hawai`i Space Grant Consortium, Hawai`i Institute of Geophysics and Planetology, University of Hawaii, 2001

AIR CANNON
Created by Dale Olive and Randy Scoville
Future Flight Hawai`i instructors

Demonstration at a glance:
By tapping the open end of a box or garbage can wrapped in plastic a pocket of air is shot out of a hole cut in the opposite end. This blast of air is used to put out a candle located 15-20 feet away.

Set-up:
I use a small plastic garbage can but a box can be used just as easily. Tightly tape or secure a thick garbage bag over the opening. If you can find a piece of rubber, it works better and is more durable. On the bottom of the can I cut a hole with approximately a six inch diameter. By tapping on the plastic, you can generate a blast of air coming out the hole on the other side.

Theory:
When you tap on the plastic, you compress the air inside the can. This compressed air is forced out the hole in the other side. This blast of air can travel great distances.

Extension:
If you can obtain a way to make smoke safely, they do sell devices in catalogs, you can fill the can with smoke and then tap it. Smoke rings are created that maintain their integrity for long distances. This allows you to see where the blasts of air are going and thus improves your aim. You could even fill the can with perfume and shoot balls of perfume at students. I sometimes use it to "shoot" students who put their heads down in class. Very few repeat that mistake a second time???


Index of Activities.

http://www.soest.hawaii.edu/spacegrant/ScienceDemos/
Communications: Hawaii Space Grant Office
This activity is featured in Future Flight Hawaii, a K-12 Education Project of Hawaii Space Grant Consortium.
FEB 27 2001.