Originally posted by Rob:
how many times can a wave of light reflect or refract off a surface before being converted into heat or something else? Or does it just 'bounce' for ever?
I remeber I once asked my physics teacher what would happen if you were to light a peice of magnesium in a closed box where the edges were all mirrors and then opened it long after the magnesium had burned out. She said you would not see light because it would have been converted into heat.
I too have been wondering about this. It sounds a bit dodgy to me.
Does the act of bouncing off a mirror automatically convert part of a photons energy into heat? If so, how many reflections does it take to convert a photon 100% into heat? If the light has lost energy to heat, wouldn't it then appear red-shifted?
Is there any difference in the light you see directly from a source 10 feet away as opposed to light reflected in a mirror 5 feet away from the source and 5 feet away from the viewer?