scjones@thor.UUCP (Larry Jones) (09/12/90)
In article <1990Sep6.002506.3313@wsrcc>, wolfgang@wsrcc (Wolfgang S. Rupprecht) writes: > I don't know anything about that, but a really neat effect occurs when > eating something extremely crunchy such as taco chips in front of a > CRT. Seems that the brain can compensate for a shaky optical > platform, but is really a loss when the viewed object changes rapidly > as a function of time. Try it. The picture really distorts. Another interesting effect can be seen by humming the lowest tone you can (the closer to the vertical refresh rate the better) while looking at a CRT. The whole screen will "swim" at the beat frequency. ---- Larry Jones UUCP: uunet!sdrc!thor!scjones SDRC scjones@thor.UUCP 2000 Eastman Dr. BIX: ltl Milford, OH 45150-2789 AT&T: (513) 576-2070 We seem to be out of gun powder. -- Calvin
mmm@cup.portal.com (Mark Robert Thorson) (09/20/90)
Here's a recent letter I received reinforcing my contention this is an
electronic -- not perceptual -- phenomenon. You armchair skeptics must
be imagining I'm opening the can by biting it with my teeth, or something.
Recent experiments seem to indicate the repeatability of the phenomenon is
not as high as I said it was in my first posting. I've blown a whole
six pack without getting a hit.
------------------------------------------------------
[Reproduced with permission.]
From: collins_t@apollo.com
Date: Fri, 14 Sep 90 15:02:06 EDT
Subject: Beer can physics
To: mmm@cup.portal.com
Hi Mark,
Everybody who has ever used a radio-control airplane knows that
you can get radio interference ANY TIME you have metal rubbing
against metal. In the RC field this is common knowledge: whenever
you rig a new plane you have to check to see that the servoes and linkages
don't cause "glitches." They show up when you move the control stick on
the transmitter a bit and the control surfaces keep twitching even after
you stopped moving the stick. Usually the cure is to eliminate the rubbing
or relocate the antenna. At extremely close range it is easy to
interfere with the signal.
Why? There must be small currents being produced in the surface of the
metal when it is stressed. The circuitry seems to be plenty sensitive
to pick it up. I bet you could get strange behavior from an RC plane
if you opened a can of beer next to it (when it is on the ground!)
Best wishes,
Tim