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Old Aug 2nd 2015, 07:30 AM   #1
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Light and plane mirror

Assuming a candle in front of plane mirror the following happens - - - photons from the candle stikes the atoms of silver oxide coated on the back of plane mirror and gets reflected off, my question is does the photon carry the image of the candle with it? Secondly why when we move the plane mirror up the image formed on the plane mirror moves down? Thank you
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Old Aug 3rd 2015, 02:45 PM   #2
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A single photon does not carry the image
the image is constructed from many photons.
The lens in your eye acts to select only those photons that have travelled from the candle to your eye at precisely the correct angle to form an image of the candle on the retina at the back of your eye.
Photons that are slightly out of line will create a blurred image,
Your eye is constructed in such a way that photons that are way out of line will be blocked out by the relatively small opening of the pupil of the eye.
This is why objects look in shaper focus in bright light than in dim light, because your pupil closes up smaller in bright light, discarding more of the out of line photons.

The movement of the image with the movement of the mirror is just down to the geometry.
In "normal" circumstances the photons travel in straight lines (i.e. when they are not being bent by a lens or reflected by a mirror etc).
If you imagine throwing balls straight at a board, they will bounce straight back.
if you tilt the board, the balls will bounce off at an angle.
A similar effect happens with the mirror, if the mirror is tilted, the photons bounce off at an angle.
Thus you see the image as having moved.
You have GOT to Laugh !
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Old Aug 4th 2015, 05:48 AM   #3
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Thanks for reply, can you please be more precise, in understanding image formation on a plane mirror, from candle photons travels and strike plane mirror->then photons react with electrons on plane mirror>some photons with same wavelength as the yellow light of candle gets reflected > then strikes eye and photo chemical changes take place then brain perceives.
Is that correct so far?

2).if the plane mirror is tilted, the photons from the candle strikes at a differrent place on the plane mirror and then strikes eye at differrent place so appears at different location is that true?
3)if the plane mirror is tilted upwards why the image of the candle formed moves down wards?
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Old Dec 21st 2015, 08:02 AM   #4
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Light and Plane Mirror

"Forgive an old and foolish man
Whom dreams delight and passions please ... "

I do not bnelieve in photons and they are the cause of puzzlement here.
The Silver backing (not silver oxide) absorbs the energy of an incident light wave in the same manner as does an aerial array with an e-m wave. It then re-radiates that energy in a form that depends on the natural resonance frequncies of its structure. An incident wave will energise the silver in a progressive wavefront that is the basis of re-radiation such that the angle-of-incidence must equal the angle at which the "reflected" wave "emerges".

Aerial arrays are much easier to understand than their high-frequency optical cousins.

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