Diana Hall, St. Charles North HS, Illinois

My students have fun predicting which canisters will get knocked down in an interference demonstration. We stretch out a long spring across the classroom floor. We then line up film canisters (or other substitutions) alongside the spring. Students predict which ones will get knocked over and which will be left standing. They must also say why.

Constructive Interference



Destructive Interference

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Column Editor: Ernie McFarland, Physics Department, University of Guelph, Guelph, Ontario, N1G 2W1

Tags: Waves and Sound