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Suppose you have a hollow box. The inside surface is made of mirror. One of the faces of the box is hinged so it can be opened and closed. If you shine a light inside it, and then close the lid, will there still be light inside???! The mirrors should be reflecting the light off each other and keep it in the box forever... shouldnt they?
Your theory is mostly good, but the problem would be that light is fast
There is absolutely no way that you could close the box and 'catch' the
light. And even if you could, you'd have to have perfectly reflective
mirrors. Real mirrors can't really reflect all
of the light
that hits them - it's inevitable that at least a few light waves will
get absorbed each time. The same goes for the corners, edges, and seams
of the box... If even the tiniest bit of light can be absorbed at any
spot, all of the light will be absorbed, since it bounces around in the
box so fast.
(republished on 07/28/06)
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