Created by Dale Olive and Randy Scoville
Future Flight Hawai`i instructors
Demonstration at a glance:
Two cans are held up and blown between creating an obnoxious sound.
All you need is two empty soda cans. Hold the cans between your thumb and middle fingers. By holding them together lightly and blowing between them you create the sound. You may or may not want to show your students this one! It is very easy to do and makes a loud obnoxious sound which may be heard all over campus soon after????
By blowing between the cans you create low pressure according to the Bernoulli principle (see Bernoulli demos.) The higher pressure outside the cans causes them to collide and vibrate off eachother which is what makes the sound.
Any of the Bernoulli or sound demos go good with this one. Another Bernoulli demo I do with cans is called the "Can Roller." This is done by placing two empty soda cans on 15 to 20 straws. By blowing between the cans they move towards each other because of the low pressure between them and the higher pressure outside of them.
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.