Can a black material reflect light when heated to incandescence?

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SUMMARY

True black materials absorb all wavelengths of visible light, while true white materials reflect all wavelengths. When a black material is heated to incandescence, it emits all visible wavelengths as white light. However, even when light is shone on this incandescent black material, it continues to absorb all incoming light rather than reflecting it. This behavior is consistent with the properties of a perfect blackbody, which is not fully represented by the sun due to its non-ideal characteristics.

PREREQUISITES
  • Understanding of blackbody radiation principles
  • Familiarity with the concept of incandescence
  • Knowledge of light absorption and reflection properties
  • Basic physics of thermal emission
NEXT STEPS
  • Research the properties of perfect blackbodies and their thermal emission characteristics
  • Explore the differences between black and white materials in terms of light interaction
  • Study the concept of emissivity and its relation to material color
  • Investigate the spectral characteristics of light emitted by incandescent materials
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Physicists, materials scientists, and anyone interested in the principles of light absorption and emission in relation to thermal dynamics.

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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