Here's a strange thought: I wonder if the electrostatic repulsion effect
in the 3M factory was caused by a gradient in air pressure.
When tape peels from a spool, the tape becomes charged. The opposite
charge is deposited not on the spool, but instead as air ions. Think
about it. If you pull ten feet of tape off a spool, the tape is strongly
charged, but the small spool doesn't become hundreds of times more charged
than the large tape. The opposite charge is mostly ions.
The 20ft wide sheet of plastic carries one polarity of charge, the air
carries the other. I'd expect the charged plastic to attract the
oppositely-charged air into the "tent" area, where charged plastic covers
the ceiling and two walls.
IONIZED AIR IN A CHARGED PLASTIC TUBE BECOMES PRESSURIZED?
Might this attraction be large enough to cause a variation in the pressure
of the air inside the 20ft space? It would only take a gradient of a
fraction of a PSI per ft. to stop an adult human from going forward, no?
Like hurricane-force winds, but with just the pressure without the flow.
The human can't move forward because the attraction between the air and
the plastic is stronger that that between the plastic and the human.
If true, what a bizarre effect. A bubble of electrically-pressurized air
which can apply many Nt of force to an object. I wonder if it could
levitate an object if the whole assembly was upended.
This brings to mind many experiments to try using an ion source and a
charged plate. Fill a metal bucket with ionized air and try to levitate
some styrofoam peanuts? Would it work if the bucket was charged opposite
the ion polarity? Or, show that a charged sphere causes the usual
inductive attraction of a pithball pendulum, then coat the sphere with
ionized air and see if pressure gradients cause reduced attraction or even
repulsion of the pith. Does ionized air tend to be attracted to grounded
conductor surfaces, thereby raising the air pressure and density near
them? If these ion-induced pressure differences are real, can a Schlerien
(sp?) optical system display them? If so, interesting things should
happen around the shadow of a pair of parallel plates which are immersed
in ionized air and then suddenly connected to a high voltage supply.
One convenient source of ions is a VandeGraaff machine with a needle or
bent paper clip taped to the side of the dome. I won't have time to try
any experiments until next weekend. Anyone want to give these a shot?
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