In reply to:
<<sympathetic vibration>>
While we're on fun experiments you can do at home, has anyone ever done the triboluminesence bit? Apparently, if you pop a wintergreen lifesaver (gotta be wintergreen, according to the pros) in your mouth facing a mirror in a darkened room and bite down on it with your mouth open, you should see a flash of light. I invested in two rolls of lifesavers with disappointing results. But triboluminesence is a real phenomenon and a physcist tells me there's no reason it shouldn't work. [honest emoticon]
It really, really works. Here's why, courtesy of The Straight Dope:
"Step One: When you shatter the sugar crystals with your teeth, electrons (which are negatively charged) break free. As a result, the atoms in which the electrons were formerly embedded become positively charged. In what amounts to a subatomic game of musical chairs, the free electrons dash around madly trying to find a new home.
Step Two: Meanwhile, as the sugar crystals disintegrate, nitrogen molecules from the air attach themselves to the fractured surfaces. When the free electrons strike the nitrogen molecules, they cause the latter to emit invisible ultraviolet radiation, along with a faint visible glow.
Step Three: The UV radiation is absorbed by the wintergreen flavoring, methyl salicylate. This then emits the fairly bright blue light you see."
-- http://www.straightdope.com/classics/a1_129.html
I can verify the theory, having tested it empirically. If you've had trouble getting the expected results, here are some suggestions. (1) Make sure that the wintergreen lifesavers you are using are fresh. Older ones which had absorbed moisture won't snap sufficiently when bit to create the shattering of sugar crystals required to generate the reaction. (2) Be sure to be in an absolutely dark space, as the light is faint and it easily obliterated by competing light sources. (3) Give your eyes time to adjust to the darkness before attempting to view the show. Happy crunching.
