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Author Topic: How can black objects absorb all light?  (Read 15210 times)

Offline ATremor

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How can black objects absorb all light?
« on: 26/07/2010 17:12:20 »
I don't understand how no visible light is reflected. Thank you


 

Offline tommya300

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How can black objects absorb all light?
« Reply #1 on: 27/07/2010 03:30:30 »
.
I don't understand how no visible light is reflected. Thank you

You have two questions that are related, but can only be satisfied by two individual answers, as far as I can see.
 I may be incomplete with my findings and comments, I am sure someone will pickup and run with it.
In reverse order.

 1.Q) I don't understand, how no visible light is reflected?
 2.Q) How can black objects absorb all light?

I found this note in my searching.

1.A)  "Objects appear black when they absorb light of ALL visible frequencies. Some objects
    that aren't black can appear black in certain situations. Stacked razor blades, for example,
    can appear black in areas because the light is just absorbed after being reflected by the
    shiny surface so much! Black objects do not absorb ALL the light that falls on them, for
    there is always some reflection at the surface. If there was no reflection, you wouldn't be
    able to see them at all!"

http://quizlet.com/1647548/physics-color-flash-cards/

2.A) Many things happen when an object is exposed to light. Let's Look at one item, staying in the frame of the color
      spectrum.

Since black is the presence of all colors, not perfect, some shades may be offset or not present. We know white light contains the full spectrum of frequencies related to these colors.
Along the range of the color spectrum, can we think of a black object, simulating an antenna, resonating at these frequencies?
When the surface of the black object is exposed to white light, all these colors are like individual tuning forks. Some resonance will begin exchanging the electromagnetic energy of these frequencies into heat and the object gets warm. That electromagnetic wave is being absorbed and are not being reflected.
Since there is no absolute mechanism known to man, the non absorbed electromagnetic wave forms of the remaining white light, must of been reflected in this processes.
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How can black objects absorb all light?
« Reply #1 on: 27/07/2010 03:30:30 »

 

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