Is it possible, having a light source, a screen and an opaque object, to get: a) only a shadow; b) shadow and partial shade; c) only partial shade? How to do it?
a) to obtain only a shadow, it is necessary to place the source as far as possible from the object, and the object as close as possible to the screen; b) if the source is not point, then by adjusting the distance between the source and the object and the object and the screen; c) only partial shade can be obtained only if the size of the source is much larger than the size of the object.
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