pwb@trw-unix.UUCP (07/08/83)
A question for the physics and chemistry types out there. The other morning
I was opening a CURAD (tm) bandaid and thought I saw something other than
the glue parting as I opened the bandaid. I pressed the two paper halves
(of the cover) back togeather, went into a bathroom with no windows, shut the
door and reopened the bandaid. What I saw was a distinct blueish-purple light
along the line of separation of the two paper halves. Also, the light is
brightest where the adhesion of the glue is the strongest (i.e. along the
edges). Static electricity? If so, what is it about glue being pulled apart
that causes the static electricity?
Phil Bonesteele, TRW E&DS
{decvax,ucbvax}!trw-unix!pwbpgf@hou5f.UUCP (07/12/83)
The light-emittance phenomenon can also be seen with certain kinds of tape (like Scotch). Unwind a bunch of it in a dark room, and you can see a glow where it pulls off the roll. A much more fascinating light show can be seen by standing in a darkened bathroom in front of the mirror. Pop a Wint-o-green Lifesaver candy in your mouth, and chew with your mouth open (the light's are out, no one will mind...). Watch the sparkles fly! (I wonder how the first person discovered this one?)
esj@ihuxl.UUCP (07/12/83)
Believe it or not, you vcan get the same effect by crushing a wintergreen Lifesaver (TM) with your molars. Go into your bathroom, turn off the lights, pop a wintergreen, turn toward the mirror, open your mouth, and crunch hard. Voila! A flash of light is emitted. This is caused, according to a guy I know at Los Alamos, by energy being released when you break the bonds in whatever noxious compound they put in wintergreens. I'm willing to take any number of bets ($5.00 max) that this is an easily reproducible effect. Chicago area only please. ***WARNING*** Standing in the head with the lights out and a roll of Lifesavers is NOT something to endear you to your roommates, etc. Jeff "Waiting for some easy money" Johnson
steve%brl-bmd@sri-unix.UUCP (07/14/83)
From: Stephen Wolff <steve@brl-bmd> There was an account of these effects within the past year or so in the lay press: CURAD tape, `friction' (old-fashioned electricians') tape, Wint-O-Green lifesavers, the lot. Possibly the Amateur Scientist column in Scientific American, but I seem to remember the science correspondent of `All Things Considered' and Susan What's-her-name together in a darkened closet on PBS. Anyone remember better?
RHB%MIT-MC@sri-unix.UUCP (07/14/83)
From: Robert H. Berman <RHB @ MIT-MC> There was an article in the last few months in the New York Times Tuseday Science section of stress-induced luminensence in a variety of materials. Some sugars, i.e. mint-flavored lifesavers, some polymers, i.e. scotch tape, are good candidates for this phemonenon. Basically, the luminesece is the result of electron transitions in outer non-spherically symmetric bands caused by stress that appear in the near-visable wavelength ranges. Related phenomena are piezoelectric materials whose conductivity (polarization) Changes when bulk forces are applied.
pds@uvacs.UUCP (07/14/83)
This Wintergreen-Lifesaver and roll-of-tape phenomenon was
documented and explained in "The Amateur Scientist" section of
Scientific American a while back. I do not recall the reference, but
if anyone is interested in skimming the indexes, I am sure that it was
not more than 4 years ago.
Dave Stotts, Univ. of Virginia
uucp: ...decvax!duke!mcnc!ncsu!uvacs!pds
CSnet: pds@uvacs
Arpa: pds.uvacs@udel-relaydonald@utcsrgv.UUCP (Don Chan) (07/15/83)
A slight correction to an article mentioning the glow observed when pulling tape off a roll and the glow observed when crunching lifesavers in the dark. I am fairly certain that the glow mechanisms are totally unrelated. I believe the tape glow is due to static electric discharges (if you look closely you can see the jagged sparks). On the other hand, crunching lifesavers (or smashing large sugar crystals with a hammer) produces light via what is know as "triboluminescence". To make a long story short, those interested should look in the Amateur Scientist column of Scientific American (I forget the exact date, but sometime in the last 10 months), which has an excellent description of the phenomenom Don Chan