Electrons and Energy
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Electrons can absorb,carry and release energy. A good illustration is fluorescence. If you've seen clothes or posters glow under a "black light" you have seen a demonstration of this phenomenon , Basically what happens is that high frequency light, say ultraviolet light(UV)(See the spectrum) hits an atom or molecule and encounters an electron. The electron's energy level is shown on the left hand diagram by the pink circle, the small dark circle is the rest of the atom. A photon of UV light encounters the electron and the electron is raised to a higher energy level. Large greenish circle, middle diagram. Then the electron falls back to its original energy level and as it does so radiates some light, at a lower frequency. Since this light is visible, the object appears to glow or fluoresce.
This is what happens when you shine a UV light("black" light) onto a day glow poster such as you might see at a party or a club.
Another illustraion of the electrons absorbing and carrying energy is photovoltaics, the conversion of light energy into electrical energy.
pgd revised 2/17/01