Body & Soul2 mins ago
glow in the dark and fluorescent
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For more on marking an answer as the "Best Answer", please visit our FAQ."glow in the dark" is a result of either phosphoecence or chemi-lumonescence. These are long lived processes. Fluorescence is a short lived process (usually less than a few hundred nanoseconds in half life) - ie there is not enought time after tunring the light off to notice an emission (without special equipment!). The two processes - phosphoecence and fluorecsence occour through similar excitations emission paths, however the former is not 'allowed' quantum mechanically and therefore a metta stable state exists wich results in the long lifetime. Chem lumin is slightly more complicated - its what goes on in "glow sticks". Sorry it got a bit complicated, but I thought I would get it all down.
Phosphorescence - 'glow in the dark' a long lived emission process - Light is absorbed and re-emitted over a few microseconds to minutes.
Fluorescence - a similar, but quicker process wich is not 'long lived' enough to be seen visually after you turned the light out.
(I could expain in more detail and simply if I could draw you some pics!) Hope this helps. Kempie is right, just beat me to it!