Why Does Light Go Through Some Materials And Not Others. A Diamond Is More Solid Than A

[guitpic]

Why does light go through some materials and not others. A diamond is more solid than a brick and a slab of hard glass more solid yet the glass and diamond passes the light.
(Dont say cos its transparent thanks)

[kawakiri]

http://www.dandydesigns.org/id58.html

[Baldric]

I think that link basically says it's transparent!

[kawakiri]

And that will be the answer.

[woofgang]

ermmmm....because some things are more see through than others? I suspect the techy answer is to do with what things are made of and how those ingredients are put together.

[KARL]

This can serve as a start, but you can do your own search:

http://physics.stackexchange.com/questions/7437/why-glass-is-transparent

[KARL]

For example, this is more "technical":

https://en.wikipedia.org/wiki/Transparency_and_translucency

[kawakiri]

Hope this link works.

https://www.youtube.com/watch?v=Omr0JNyDBI0

[Togo]

Photons pass through glass because they are not absorbed. And they are not absorbed because there is nothing which "absorbs" light in visual frequencies in glass. You may have heard that ultraviolet photons are absorbed by glass, so glass is not transparent for them. Exactly the same happens with X-rays for which our body is nearly transparent whilst a metal plate absorbs it.
All photons have a certain frequency - which for visible light is related to the colour of light, whilst for lower or upper frequencies in the electromagnetic spectrum it is simply a measure of the energy transported by a photon. A material's absorption spectrum (which frequencies are absorbed and how much so) depends on the structure of the material at atomic scale. Absorption may be from atoms which absorb photons (remember - electrons go to upper energetic states by absorbing photons), from molecules, or from lattices. There are important differences in these absorption possibilities:
Atoms absorb well-defined discrete frequencies.
Molecules absorb discrete frequencies but there are many more absorption lines because even a simple molecule has many more energetic levels than any atom. So molecules absorb much more light.
Crystalline lattices may absorb not only discrete frequencies but also continuous bands of frequencies, mainly because of discrepancies in the crystalline structure.
It is all down to the molecular and atomic properties of materials in the light spectrum. The light spectrum that our eyes have evolved to detect. Beings from other worlds, if they exist, may be able to 'see' through steel or concrete..

[Peter Pedant]

some quite good answers
it used to be one of the things that bright young students were asked at Oxbrdige entrance interviews

I got ' if you cool something why does it get brittle ? ' and floundered hopelessly .....

[guitpic]

Thanks for the answers

[Rev. Green]

IF you read Feynman's lectures the answer is quite surprising. Light goes straight through all objects. When light hits a mirror, for example, it excites the first layer of atoms and they radiate in all directions. The radiation which happens to be in the same direction as the incident beam is out of phase with it, so the next layer of atoms receives the original light, plus an out-of-phase component, and the process of excitement and radiation continues. You can view this in two ways: either the initial beam is gradually absorbed, or the initial beam passes straight though accompanied by out-of-phase components which exactly cancel it out.

[Matheous-2]

Just to add my very limited 2p worth....Humans can only 'see' less than -1 20trillionth of the known electromagnetic spectrum. Rather limited!

[Peter Pedant]

I thought we had had this
was it on;y a fortnight ago ?