A mechanical analogy for the photoelectric effect

Analogy is a potent tool in the teacher's repertoire. It has been particularly well recognized in the teaching of science. However, careful planning is required for its effective application to prevent documented drawbacks when analogies are stretched too far. Befitting the occasion of the World Year of Physics commemorating Albert Einstein's 1905 pioneering contributions to the understanding of the photoelectric effect, a suitable mechanical analogy for introducing this effect to high school students is described in this article. Cost-effectively, it allows students to comprehend the photoelectric effect by relating it to their visual experience from the mechanical world with which they are familiar. © 2006 IOP Publishing Ltd.