How does Transparency?

[sergey500]

Yeah I got it, it lets light through. But how? This is what i don't get.

 

You still have a solid shape (I am not refering to most gases), assuming its transparent there is no colors on it, thus nothing comes back to your brain. But wouldn't you see black? How does light pass through the solid object without changing any properties? :lol:

 

Wiki told me Examples of transparent materials are air and some other gases, liquids such as water, most glasses, and plastics such as Perspex. Where the degree of transparency varies according to the wavelength of the light, the image seen through the material is tinted. This may for instance be due to certain metallic oxide molecules in glass, or larger colored particles, as in a thin smoke. If many such particles are present the material may become opaque, as in a thick smoke.

 

Now I must be quite dense, but I did not understand that. What do does wavelength of light have to do with anything?

 

Anyways. So clear this up for me how does light pass through solid object without altering their prooperties?

 

Oh while I am on subject of transparency, since glass is tansparent, I heard glass is actuelly a fluid, is this true? :lol:

[GAHD]

You may wish to learn about refraction, and how a prism works :lol: that'll lead you to the answer.

[sergey500]

Hm? Refraction is a distortion in a reflected object, usually caused by a change in the speed of light. Such as pencil being refracted in glass of water. So how will lead me to my answer? And prism? ...why?

 

Can't you just give me the answers here.

[CraigD]

Can't you just give me the answers here.[?]

OK. For questions like this, its more important that you understand the answer, than finds it for oneself - thought finding it the hard way makes it surerer that really understand it.

 

Light consists of one or more photons, a kind of fundamental particle called a boson.

 

A transparent solid consists of many fundamental particles – electrons, quarks, and several kinds of bosons, including photons – arranged into atoms.

 

There are at least 2 ways to consider how the photon(s) passing through the transparent solid interact with the electrons, and the electrons in turn interact, with the Quarks in the nuclei of the atoms. A complicated, intensely mathematical way is to consider every particle to be a quantum wave function, and describe how these wave functions modify one another. Though this way is more technically true, a more intuitive way is to imagine that these particles are objects like those in our everyday experience – pool balls, etc. – and describe the interaction as the electrons absorbing and emitting the photon(s) many times as the photon(s) pass through the solid.

 

Assuming the photon(s) are under a certain energy (Energy =~= Frequency), they will not break (ionize) any electrons free of the atoms. At least, it will be absorbed by a particular electron, and almost immediately reemitted, with the same frequency, direction, and other attributes. Although, from a quantum Physics point-of-view, it isn’t exactly the same photon, it very nearly is, and for our discussion, can be considered the same photon.

 

However, if the photon has one of exactly the right frequencies, it can be absorbed by an electron, and the electron settle into a new, higher-energy “orbit”, which is really to say a new interaction with the quarks in its nuclei. This state usually won’t last long, but it last much longer than the “almost immediately” of the previous case. Eventually, the electron will settle into a lower-energy orbit, and emit a photon, but this photon is very different than the one(s) that boosted the electron into the higher-energy orbit – it may have a different frequency, direction, etc. For photons of these particular frequencies, the solid isn’t transparent at all, but opaque, meaning that the photon(s) that are eventually emitted don’t much resemble the ones that were absorbed. If the emitted photons aren’t in the visible frequency spectra, but, say, in the infrared (a popular emission spectra for commonplace atoms), we say the solid is “a black body”.

 

As long as the photon(s) aren’t of any of these special frequencies for the atoms in the solid, the solid is transparent to them. The amount of additional time they spend being absorbed and almost immediately reemitted is responsible for the slight reduction in effective speed of light within that substance measured by its refractive index.

 

For a really puzzling challenge, consider the question: what is the difference between a perfectly transparent solid, and a perfectly reflective surface? Explaning this requires a little more digging into the difficult quantum wave function stuff. :lol:

[P-man]

CraigD explains it well. To explain the wavelength confusion, light comes in different wavelengths from ultraviolet to infrared. However, only seven are visible to the naked eye: the colors of the rainbow. Black and white are respectively the absence of light and all the wavelengths of light. A prism separates white light into the different wavelengths. So you see, for transparency, the wavelegths have to be able to pass through the material without getting distorted or absorbed. Because, as CraigD said, when you see a blue material, the material is absorbing all the colors except blue, which bounces back to your brain.

 

Hope this helps, I tried to get a different view at the problem than CraigD.

 

Pierre.

[InfiniteNow]

Okay... I just want to try this for a change. See what it feels like. Here goes:

 

 

Nuh uh! It's cause 'cause God made it transparent, so there! :rainbow:

[InfiniteNow]

No... That wasn't really satisfying at all. Kind of left me feeling a bit empty inside. CraigD really hit the nail on the head here. Sweet post, btw.

 

 

"Ignorance Is Bliss"

 

Ignorance is bliss, ya know it's true

Ignorance is bliss, just look at you

 

Is it goin' anywhere?

 

Ignorance is bliss, ya know it's true

Ignorance is bliss, just look at you

 

I'm alive, I'm alive, I'm alive, yeah

 

What's happening to our society?

Disintegration of humanity

Destruction of the environment

(Cram that cop donation in your ***)

 

Is it goin' anywhere?

 

??

Politicians (to confuse you)

What's good for them, now it ain't good for you

But there ain't nothing that you can do

 

I'm alive, I'm alive, I'm alive, yeah

 

Ignorance is bliss, ya know it's true

Ignorance is bliss, just look at you

Hey!

 

Ignorance is bliss, ya know it's true

Ignorance is bliss, just look at you

 

I'm alive, I'm alive, I'm alive, yeah

Go Ramones... :rainbow:

 

 

 

You raised some good points too, P-man:

 

To explain the wavelength confusion, light comes in different wavelengths from ultraviolet to infrared. However, only seven are visible to the naked eye: the colors of the rainbow.

...but just for clarity sake, more than seven wavelenghs are visible to the naked eye... in fact all of them hit our eyes in the same way and amounts. It's just that our relatively limited perceptual processes make it so we primarily distingush between just a few basic "ranges of wavelength" like "purplish" "blueish" "greenish" "reddish" etc... It all comes in just the same. It's not like we ONLY see light at 410nm, 550nm, and 680nm for example.

 

We have rod-shaped and cone-shaped receptors in our eyes that do different things in different conditions. Some fire a little electrical signal, others don't, and it's the aggregate (the combination) of their overall response that is interpreted by the brain as "Orangish".

 

 

You likely knew this already, but just so nobody else gets confused...

[arkain101]

But think about this, and think about this alot. If all we are is a functioning mass of atoms as some theories like to claim. How or why did the actuall sensation of color get created or invented.. Can atoms REALLY structure themselves to communicate the visual sensation of a color. I mean as far as an atom is concirned color doesnt exist, they just live in this coded world where they follow exact rules and act like radios as they absorb some information and spit it back out to tell every other atom who they are.

 

Somewhere along the evolution of life, HOW IN THE WORLD DID ATOMS INVENT COLOR?

 

It had to of already been created I think, it has always been, because it is generally the same for any kind of life...Not only is it strange that color was at some point invented, for lifes interest but, it also affects the emotional state of living things.. white will give you peacefull sensations... (why did armies for as long as can remember choose the white flag as a sign of peace and surrender, One wave of a white peice of material on the battle field stands out and sends such a strong message that bloodshed turns to peace and relaxation, no other color would feel right)

 

Anyway that is my 2 cents on intelligence functioning in a dimension behind the physical world.

[InfiniteNow]

arkain101 -

Without reference to the Intelligent Design concept you raised or attacking the questions you posed one by one:

Maybe it would aid in understanding if you replaced the word "color" with the word "heat" in your post.

 

But think about this, and think about this alot. If all we are is a functioning mass of atoms as some theories like to claim. How or why did the actuall sensation of HEAT get created or invented.. Can atoms REALLY structure themselves to communicate the visual sensation of HEAT. I mean as far as an atom is concirned HEATdoesnt exist, they just live in this coded world where they follow exact rules and act like radios as they absorb some information and spit it back out to tell every other atom who they are.

 

Somewhere along the evolution of life, HOW IN THE WORLD DID ATOMS INVENT HEAT?

 

It had to of already been created I think, it has always been, because it is generally the same for any kind of life...Not only is it strange that HEATwas at some point invented, for lifes interest but, it also affects the emotional state of living things.. white will give you peacefull sensations... (why did armies for as long as can remember choose the white flag as a sign of peace and surrender, One wave of a white peice of material on the battle field stands out and sends such a strong message that bloodshed turns to peace and relaxation, no other HEATwould feel right)

 

Anyway that is my 2 cents on intelligence functioning in a dimension behind the physical world.

[P-man]

That's a good point. Well we all know that a material is a colour because it absorbs all the colours of the light spectrum except the colour that it appears. So we can say that atoms invented colour by rejecting a certain wavelength of light. I am persuaded that that is how pigments work: the atoms/molecules they are made of absorbs all the wavelengths except blue, for example. Thus it is a blue pigment. Just a theory.

 

Pierre.

[HydrogenBond]

Transparency is wavelength dependant. For example, seismic waves make the solid crust of the earth transparent at that very long wavelength. That is more of an acoustical wave that does not travel at the speed of light. If comes down to the wavelength of energy and whether the atoms will absorb, reflect, or alter (refraction) it or not. The soft tissue of our bodies are almost transparent to x-rays but bones are not at that wavelength.

[P-man]

True. And the very first layer of our skin is transparent to the naked eye. As HydrogenBond said, it's a question of wether or not the atoms reflect, absorb, alter, or let the light through (transparency). Hopefully you have enought opinions to choose an answer to your original question.

 

Pierre.

[arkain101]

arkain101 -

Without reference to the Intelligent Design concept you raised or attacking the questions you posed one by one:

Maybe it would aid in understanding if you replaced the word "color" with the word "heat" in your post.

 

No that would not help sorry heheh.

 

I mean color, because, as far as an atom is concirned there cant really be color. But what gets reported to our consciousness is an somewhat deeper meaning of freqency that we see as color. But dont you see how confusing it is that a color is distinct to you? You know it, it is like flavour, can atoms really create color? or is there more involved to our existance.. this is my point.

[P-man]

As I said before, the atoms create colour by absorbing all the colours but one. In a way they do create colour, but hte original creator of colour is light.

[dagaz]

OK. For questions like this, its more important that you understand the answer, than finds it for oneself - thought finding it the hard way makes it surerer that really understand it.

 

Light consists of one or more photons, a kind of fundamental particle called a boson.

 

A transparent solid consists of many fundamental particles – electrons, quarks, and several kinds of bosons, including photons – arranged into atoms.

 

There are at least 2 ways to consider how the photon(s) passing through the transparent solid interact with the electrons, and the electrons in turn interact, with the Quarks in the nuclei of the atoms. A complicated, intensely mathematical way is to consider every particle to be a quantum wave function, and describe how these wave functions modify one another. Though this way is more technically true, a more intuitive way is to imagine that these particles are objects like those in our everyday experience – pool balls, etc. – and describe the interaction as the electrons absorbing and emitting the photon(s) many times as the photon(s) pass through the solid.

 

Assuming the photon(s) are under a certain energy (Energy =~= Frequency), they will not break (ionize) any electrons free of the atoms. At least, it will be absorbed by a particular electron, and almost immediately reemitted, with the same frequency, direction, and other attributes. Although, from a quantum Physics point-of-view, it isn’t exactly the same photon, it very nearly is, and for our discussion, can be considered the same photon.

 

However, if the photon has one of exactly the right frequencies, it can be absorbed by an electron, and the electron settle into a new, higher-energy “orbit”, which is really to say a new interaction with the quarks in its nuclei. This state usually won’t last long, but it last much longer than the “almost immediately” of the previous case. Eventually, the electron will settle into a lower-energy orbit, and emit a photon, but this photon is very different than the one(s) that boosted the electron into the higher-energy orbit – it may have a different frequency, direction, etc. For photons of these particular frequencies, the solid isn’t transparent at all, but opaque, meaning that the photon(s) that are eventually emitted don’t much resemble the ones that were absorbed. If the emitted photons aren’t in the visible frequency spectra, but, say, in the infrared (a popular emission spectra for commonplace atoms), we say the solid is “a black body”.

 

As long as the photon(s) aren’t of any of these special frequencies for the atoms in the solid, the solid is transparent to them. The amount of additional time they spend being absorbed and almost immediately reemitted is responsible for the slight reduction in effective speed of light within that substance measured by its refractive index.

 

For a really puzzling challenge, consider the question: what is the difference between a perfectly transparent solid, and a perfectly reflective surface? Explaning this requires a little more digging into the difficult quantum wave function stuff. :hihi:

 

 

Although I think this is an excellent explanation of something so fundamental I'd never really questioned it before, I was just wondering (as a high school science teacher) how I could explain this to my kids using classical (non-quantum) mechanics?

 

i.e. what is the property that allows some solids to reflect or transmit light, or to absorb certain wavelengths and reflect others?

[InfiniteNow]

Although I think this is an excellent explanation of something so fundamental I'd never really questioned it before, I was just wondering (as a high school science teacher) how I could explain this to my kids using classical (non-quantum) mechanics?

 

i.e. what is the property that allows some solids to reflect or transmit light, or to absorb certain wavelengths and reflect others?

Color is the result of an interplay between particles and waves. :hihi:

Transparency is a result of that interplay as well.

 

It's all just energy following patterns about which we continually seek to improve our understanding.

 

 

 

I guess the question becomes... how old are the kids? how much do they know already?

 

It's easier to build a house if the foundation is already in place and you know what materials you have available, but the problem changes entirely if you have to plan for the foundation as well and don't know with what materials you will be working...

[CraigD]

I was just wondering (as a high school science teacher) how I could explain this to my kids using classical (non-quantum) mechanics?

 

i.e. what is the property that allows some solids to reflect or transmit light, or to absorb certain wavelengths and reflect others?

It’s difficult to explain, beyond noting that “white” light contains many different colors, and that different substances absorb certain colors.

 

While the quantum physics of electrons in atoms absorbing and emitting photons is likely a bit complicated for most high school students (or even most college students!), the Bohr model of the atom provides a simpler approach that gives an approximation of the quantum model. Most college “modern Physics” courses teach the Bohr model as a sort of “warm up” for the full quantum physical model, (and to give a historic perspective). Your kids would likely find it not too intimidating. I recall of my school days being a little thrilled that I could learn things that nobody understood less than a century ago.