Question about light

If light has no mass then why doesn't it pass through matter?

If light is where we derive color, then why does matter and density contain color? Some theorize that all matter is condensed light in some form or another. Any thoughts on this?

The color of an object is... lets say blue for instance.... is because that is the color/hue that the object reflects.. all other colors are absorbed by the object. It is blue because that is what color it reflects off of its surface.

That sounds wonderfull, and thank you but I would like more information, a source, some explication. Sounds more like a hypothesis than the truth.

Originally posted by LastOutfiniteVoiceEternal
That sounds wonderfull, and thank you but I would like more information, a source, some explication. Sounds more like a hypothesis than the truth.

He's exactly right, in that the color reflected, its the color that your eye sees. Light can also pass through materials like glass and plastics. That's why a black t-shirt gets hot in the sun, because most of the light is absorbed. A white t-shirt reflects a wide spectrum so it stays cool.

Thank you both and sorry for my half way assumption. Could you go into more depth please? Such as frequencies and moreso? Also, in absence of light my white shirt is still white. Could you explain this?

A white T-shirt in total darkness is still made of the same reflective materials that allow white colord light to be reflected. There just isnt any light for this to take place. Now.. if you were to filter out all the light spectrums/hues/shades that the T-shirt reflects then you most likely will see a totally black T-shirt..... because all the light that would normally be reflected are completely absent and all the other present light would be completely absorbed by the shirt.

Here is something else to think about.... sorta off topic... but not really..


The speed of darkness is the same as the speed of light.

There are thousands of sights on the Internet that explain the relationship between color & light.

Here is one of the first ones that popped up when I googled it:
acept.asu.edu...

homeschooling.gomilpitas.com...

www.learner.org...

If there is no light then your White T shirt is not white. Color exists because of light.

The speed of dark is equal to the speed of light only of the fact that it appears in reciprocation to the speed at which light retracts from an area leaving darkness. But darkness itself is only the absence of light, not a presence of photons.

What I am saying is that my white t-shirt, in total absence of light, whether I can see it or not, is still going to be white... whether there is light or not. The material is white. Why is the material white? What gives material color?

(btw, I liked the speed of dark comment , things I have thought of before also)

How much time do you have?

You can go to google video and search for "Physics 10 - Lecture" and you find a whole bunch of in depth lectures about light from the University of Berkeley.
All the question you asked above and more are answered. Look for lectures "14" and up.

Originally posted by Sparky63
If there is no light then your White T shirt is not white. Color exists because of light.

That's not completely true. Color optically exists to our eyes because of light. But when I turn the light off in a dark room the color doesn't suddenly leave the walls. I want some ATS member input and fresh thoughts. But thank you for the sites. I have read just about all that I can... I'm looking for more.

[edit on 7-11-2007 by LastOutfiniteVoiceEternal]

If colour (or color as you guys call it) can only be seen because of light, why do we see colour on our computer screens?

How would you make a certain letter/number/button have a different surface that absorbs and reflects light in a different way to give off different colours

Sorry if its a bit of a dumb question

Okay, thank you all. Light gives everything color through reflection and in the dark the material that reflects is still there, just lacking the light that is needed to be reflected.

I think the word you are looking for is "material" not color when refernceing the dark room scenario. Your T-shirt is still the same "material" that reflects white light. This is true... however there is no light present for it to reflect the color you see with your eyes.

Remember... the material of something is what reflects the light it does not absorb.

Originally posted by LastOutfiniteVoiceEternal
The speed of dark is equal to the speed of light only of the fact that it appears in reciprocation to the speed at which light retracts from an area leaving darkness. But darkness itself is only the absence of light, not a presence of photons.

What I am saying is that my white t-shirt, in total absence of light, whether I can see it or not, is still going to be white... whether there is light or not. The material is white. Why is the material white? What gives material color?

(btw, I liked the speed of dark comment

, things I have thought of before also)

I don't know if this is the answer you're looking for but, I white shirt reflect all the colors and red, blue, green, etc. Your eyes see all the colors blended together as white. So all atoms reflect differently and depending what atoms and molcules and/or dies are used when making the shirt they will reflect light based on the atoms. All elements reflect differently and depending on the combination of elements it veries the reflected colors.

So, what are the objects doing with this energy/light that they are absorbing instead of reflecting? Where does the rest of it go?

Heat.

The light absorbed is radiated back as heat.

Originally posted by LastOutfiniteVoiceEternal
So, what are the objects doing with this energy/light that they are absorbing instead of reflecting? Where does the rest of it go?

Well this is were have to watch the videos from the University of Berkeley, but without getting too detailed, in short materials store the energy as heat, and over long periods of time causes the materials to start to break apart (mainly UV light does this). Like a coke can in the sun starting to fade, but mostly heat.

[edit on 7-11-2007 by ebe51]

Originally posted by LastOutfiniteVoiceEternal
That's not completely true. Color optically exists to our eyes because of light. But when I turn the light off in a dark room the color doesn't suddenly leave the walls.

Really? How odd. When I take my white t-shirt into a completely dark room, I no longer see a white t-shirt. Instead I see darkness all around me.

Okay, cool, or hot! Thanks, you all have been so very helpfull.

So we're in to the cycle. Light creates heat, heat vibrates, heat creates light.

This slow vibration over time assists in deterioration. Okay, I'll get around to those videos. Sounds interesting... I swear I thought I once knew all of this... in fact I can remember writing about it and picturing it in my head... how weird... the trauma of a relationship can sometimes steal all the memory and knowledge right from ya... huh.

Heat, light... light, heat... vibration. The cycle of eternal energy, 100% efficient.

So if we had an ultra sensitive heat sensory unit we could actually measure how much energy and heat the objects were taking in and giving out. So... the spectrum of light that can be reflected is reflected, and the type that can't is, for the most part, reflected off as heat. And when you say "radiated" I suppose you aren't referring to actual radiation as in radio active energy? Okay, I'll get to watchin' those videos later today. Thank you guys/gals... ah heck, thank you entities of consciousness! There... that should cover all of you.