Can a black material reflect light when heated to incandescence?

AI Thread Summary
True black materials absorb all wavelengths of visible light, while true white materials reflect them. When a black material is heated to incandescence, it emits all visible wavelengths as white light. If light is then shone on this incandescent black material, it continues to absorb all light rather than reflecting it. The discussion highlights that even though the material emits light, it does not change its fundamental property of absorption. The comparison to the sun indicates that while it emits more light than it absorbs, it is not a perfect blackbody.
theobromine
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True black materials theoretically absorbs all wavelengths of visible light. True white materials reflect all wavelengths of light.

If a material which was black at room temperature was heated up to incandescence so that it was emitting all visible wavelengths (white light), and then light was shone at the material, would it:

a) Absorb all light, as it was black when not incandescent
or
b) Reflect all light, in essence behaving as a white object

Insight would be much appreciated!
 
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theobromine said:
Summary: True black materials theoretically absorbs all wavelengths of visible light. True white materials reflect all wavelengths of light.

What happens when a material which is ordinarily black is heated to incandescent?

If a material which was black at room temperature was heated up to incandescence so that it was emitting all visible wavelengths (white light), and then light was shone at the material, would it:

a) Absorb all light, as it was black when not incandescent
It still absorbs all light. If you shine a flashlight on the sun it does not reflect off the sun. It is brighter than your flashlight because it emits more light to the flashlight than it absorbs from the flashlight, but it does not reflect or scatter your flashlight.
 
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Dale said:
It still absorbs all light. If you shine a flashlight on the sun it does not reflect off the sun. It is brighter than your flashlight because it emits more light to the flashlight than it absorbs from the flashlight, but it does not reflect or scatter your flashlight.
Thanks, that's helpful.
 
Dale said:
If you shine a flashlight on the sun it does not reflect off the sun. It is brighter than your flashlight because it emits more light to the flashlight than it absorbs from the flashlight, but it does not reflect or scatter your flashlight.

Just a little correction: this statement is not really accurate because the sun is not a perfect blackbody. It is true if we replace the word sun with perfect blackbody at several thousand Kelvin.
 
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