Purpose:Classic illusion of penny levitating above a pair of parabolic concave mirrors
Description:This commercial apparatus forms a real image of a penny glued to the bottom mirror. Two concave parabolic mirrors with the correct focal length and spacing create an image of the penny levitating on the opening of the upper mirror. The illusion can be viewed within a limited angle, so it is most effective for individual observation. A ray drawing is included which shows how the image is produced.
Invite students to place their hand through the image, to get a feel (or not) for what's happening. Have them consider where such images might be used.
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Last modified on Tuesday, 22 August 2017 14:22