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I've read that all electrons want to be in their ground state, so when light from a source is absorbed by the electrons in a red colored object and forced the electrons into higher orbital/energy state. The excited electrons would then lose the equal amount of energy it gains earlier so as to go back into ground state, so this same energy is the exact same photon coming from the light source. Since the photon originate from a light source and relay into our eyes with the same amount of energy as initially, what happens if we shine a blue colored laser at the red object?

user6760
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    The object is red because it absorbs all other wavelengths more than it absorbs red, which gets reflected. The blue and green parts of the spectrum get converted into heat. The process in solids is more complex than in atomic physics because more than a single atom is involved in it, which allows the conversion of light (photons) into phonons (quantized oscillations of the solid's lattice). – CuriousOne Jan 16 '16 at 00:25
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    "The blue and green parts of the spectrum get converted into heat." Why, and how? Why would "the object" even bother about "all other wavelength"? – Gyro Gearloose Jan 16 '16 at 00:35
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    Could you make this an answer @CuriousOne? – untreated_paramediensis_karnik Jan 16 '16 at 00:35
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    @no_choice99: Jen is too eager to get some points. She gets down-voted a lot, I guess. :-) – CuriousOne Jan 16 '16 at 01:03
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    @CuriousOne Well it is your answer. Just post it and flag Jen's answer for moderators. – untreated_paramediensis_karnik Jan 16 '16 at 01:08
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    @no_choice99: It's OK. She is not simply plagiarizing without even giving a proper citation. :-) – CuriousOne Jan 16 '16 at 01:10

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The object is red because it absorbs all other wavelengths more than it absorbs red, which gets reflected. The blue and green parts of the spectrum get converted into heat. The process in solids is more complex than in atomic physics because more than a single atom is involved in it, which allows the conversion of light (photons) into phonons (quantized oscillations of the solid's lattice). – CuriousOne, in a comment

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Muze
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    "The blue and green parts of the spectrum get converted into heat." Ohm, why so? Part one) why are they absorbed at all, and part two), by which mechanism, exactly, are they converted to heat and not simply re-emitted at the frequency that was absorbed? – Gyro Gearloose Jan 16 '16 at 00:42
  • @GyroGearloose http://physics.stackexchange.com/q/80919/ – Muze Jan 16 '16 at 00:49