Absorbtion,reflection,and emission.

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Humans primarily emit infrared radiation, as described by Wien's law, while absorbing and reflecting parts of visible light. For example, Smurfs reflect blue light and absorb other visible wavelengths. Emission refers to an object releasing electromagnetic radiation due to its thermal energy, whereas reflection occurs when light from another source bounces off an object. Not all frequencies of light can be absorbed; only specific frequencies lead to electronic or vibrational excitations, with the rest being reflected. Understanding these distinctions clarifies the processes of absorption, reflection, and emission in relation to electromagnetic radiation.
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I want to see if I understand these rules correctly. Us humans emit mainly in the infrared, that can be described by wiens law, but when visible radiation falls upon us, our body absorbs some part of the white light, but reflects whatever it doesn't. Smurf's for example reflect the blue part of visible radiation, while absorbing all other parts of the visible spectra.

And if emission is when an object emits electromagnetic radiation, isn't that the same as reflection? Or are they different? Is emission when it comes from the objects own thermal energy, and reflection when it comes from another object emitting it? And why is it that particles can be reflected, instead of completely absorbed and emitted?
 
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LogicalAcid said:
Is emission when it comes from the objects own thermal energy, and reflection when it comes from another object emitting it?
yes
And why is it that particles can be reflected, instead of completely absorbed and emitted?
by particles, do you mean photons?
Light of only certain frequencies can be absorbed by an object, such as the ones that cause electronics excitations, phononic (vibrational) excitations, ... These may later be emitted. The other frequencies just get reflected.
 
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