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Physics/absorption of light in plane mirrors


in a plane mirror the image is the same size as the object.and in a ordinary window pane of glass ( i.e a shop window) the image is the same size as the object but fainter because more light is my question is the absorption of light doesnt affect image size and shape.why? is this because of the millions of photons in each light beam so there is still a massive a mount of light relfected even though osme have been absorbed.and have been told the accuracy of what you see in a plane mirror depends solely on the flatness of the reflective surface and light absorbed does not affect the image size.thank you.

Not really, most mirrors absorb more light because the light has to pass through the pane of glass twice.  However, intensity is not the same as size.  Geometry determines image size.  The direction they travel and the sheer number of them are unrelated.  Imagine them as individual photons making a pattern.  Might be less paint on the canvas, if it were a picture, but the canvas is the same size...


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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