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As everyone knows, an object with color appears that way because it reflects its specific color(s). Textbooks tell us other colors are absorbed. Now, here's the question: what happens to the absorbed light?

For example, a red rose absorbs all colors except red, which is why it appears red to us (according to the widely accepted theory). But what happens to the remaining electromagnetic spectrum (EMS) the rose absorbs?

Bohr's theory explains that an electron jumps to a higher energy level after absorbing a photon with the right amount of energy. It also states that for the atom to be stable, the electron gets rid of the excess energy as quickly as possible. This implies the rose is emitting the absorbed colors. Otherwise, the rose would just keep getting hotter and hotter, which obviously doesn't happen. So why do we only see the red color and not the re-emitted colors?

If this applies to everything, everything should be glowing with re-emitted light, but they don't. Why?

As explained by Bohr, if the energy of red light is required to jump to a higher energy level, then when the electron jumps back to the lower energy state, it must release light with the energy of the absorbed red light. This statement needs clarification (see below).

Another follow-up question: As I've found, phosphor absorbs ultraviolet light and re-emits it as visible light. As ultraviolet light has more energy than visible light, where does the extra energy go? Some of it is certainly converted to heat, but not all, right? Otherwise, it would get extremely hot.

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    $\begingroup$ Visible gets converted to IR in the molecules of the rose. In large molecules there are many many energy levels for the electrons to transition to. $\endgroup$
    – PhysicsDave
    Commented Mar 19 at 14:39
  • $\begingroup$ related - possible duplicate or maybe just helpful: physics.stackexchange.com/questions/547512 (and Dale's answer) $\endgroup$
    – g s
    Commented Mar 19 at 15:59
  • $\begingroup$ Also keep in mind that objects of a certain color/s reflect that color/s more, not only. If you point a green laser (which emits only green light) at the reddest rose that ever was, you'll still see a green dot. $\endgroup$
    – g s
    Commented Mar 19 at 16:05

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The red rose does get hotter in sunlight. As it warms up it starts radiating more and more thermal energy, until it reaches thermal equilibrium. A white rose reflects more of the light, and does in fact get less hot in sunlight than a red rose. A black rose will get even hotter than a red rose before it reaches thermal equilibrium. Temperature is a directly measurable property.

If this applies to everything, everything should be glowing with re-emitted light, but they don't. Why?

They do glow with re-emitted light as can be seen by looking at them with an infra red camera.

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