Flash Physics

An attempt to help his students visualize experiments before undertaking them has led to international renown for David Harrison, a senior lecturer in the physics department.

About five years ago, Harrison came up with the idea of using homemade videos to prepare first-year physics students for experiments by giving them a “preview” of what would happen.When one of the videos didn’t turn out well, Harrison hit upon the idea of animating the experiments instead.

Using a program called Flash, Harrison created “moving diagrams” of his experiments and distributed them online.They were an instant hit among his students, and since 2002 Harrison has created more than 80 of the animations, illustrating ideas from electricity, sound, chaos and optics, among other subjects – mostly at an introductory level.“If a picture is worth a thousand words, I figured a moving picture is worth a million words,” says Harrison.

The animations vary in complexity – from showing the difference between the concepts of distance and displacement to tracking the orbits of one or more planets around two suns. Students can sometimes change parameters – such as the mass of a sun or the position of the planets – to see what effect this has on the animation.The results can be hypnotizing.“It’s huge fun,” says Harrison.“That people find them useful is a bonus.”

The animations were downloaded more than 800,000 times last year,and Harrison says he receives several e-mails a week from around the world from people who have discovered them online.Texts accompanying the animations have been translated into Spanish,Danish,Turkish, Greek and Russian,and this fall they were cited in Science, the journal of the American Association for the Advancement of Science.

Harrison is constantly revising his work, and plans to keep making new animations, as long as people find them helpful.“I always have about two or three on my ‘to do’ list,” he says. The animations can be viewed at www.upscale.utoronto.ca/GeneralInterest/Harrison/Flash