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rahuldandekar
2005-Mar-03, 09:53 AM
Well, this is a little stupid question...

When photons fall on a mirror, they are absorped and emmited by the electrond in the surface randonly. Then how come we get such a clear reflection of ours, if the electrons are emmiting light randomly?

astromark
2005-Mar-03, 12:27 PM
:rolleyes: These are langage related questions; As you have used the word 'fall' when discribing the way light ( photons ) arrive at your reflecting surface. :unsure: The word random may not in this case actually meen randomly.
I would sagest the word random in this case is refering to the random corse of the electrons about the atom. At this leval, ( sub atomic )Random could be very precise. B)

antoniseb
2005-Mar-03, 01:26 PM
Originally posted by rahuldandekar@Mar 3 2005, 09:53 AM
When photons fall on a mirror, they are absorped and emmited by the electrond in the surface randonly. Then how come we get such a clear reflection of ours
For starters, a visible light photon is thousands of times wider than atoms are. When a photon reflects off a mirror, it is not just one atom doing the reflecting. If your mirror is flat enough, it will reflect photons in a consistent direction. Really good mirrors in telescopes are figured to within 1/20th of a wavelength of the shortest wavelength they will be used for. This might easily be hundreds of atoms away from being flat.

wstevenbrown
2005-Mar-03, 06:19 PM
The clearest explanation I have ever seen is in Richard Feynman's book QED. In it, he gives a clear exposition, mostly in common English words, of why light acts the way it does in many circumstances. It's still in print, only around 150 pages long, and still a valuable resource. Best regards-- Steve

rahuldandekar
2005-Mar-04, 11:13 AM
Thanks everyone.