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cs248acct

when a surface is tilted, do we consider distance to stay the same? i.e. the effect in slide 26 is independent from this effect?

unicorn

@cs248acct When a surface is tilted, you can consider parts of it being closer to the source of light and parts farther away (i.e. at different radii away from the center of the circle/sphere of emitted light).

ecohen2

Does this distance law still hold for a lazer light - per say - that never spread out? i.e. is this distance just because there is a larger distance for the same amount of light to spread to (and the light is assumed to spread)?

arshbuch

I believe this distance law holds for anything that emits photons. You would have to go a much farther distance away to see the phenomenon but it still exists.

tbell

@ecohen2 An idealized laser beam (no spread at all, and no scattering due to airborne particulates) would not follow this inverse square law, since the area over which its flux is spread would be constant. Of course, laser beams out-there-in-the-real-world actually do spread out, just with a very very small angle. Once you get far enough away, you will be able to notice an inverse-square decay.