|
|
|
|
|
|
|
|
Static Hocus-Pocus
|
| Niels Jonassen |
When you read an ad extolling the virtues of some device
and promising fantastic results, you often wonder, "Can this
be true?" If you're not familiar with the device, you may
let it go, or maybe even believe the hype a little bitnid
moy, as they say here in Bangkok. It's a completely different
story, though, when somebody makes outrageous claims in an
area that you know well.
Over the years that I have been employed at the Technical
University of Denmark, I have experienced this scenario over
and over again, generally in one of two forms. In the first,
someone who knows very little physics skims a textbook, semidigests
it, mixes that scant understanding with a little alternative
medicine, and comes up with a gadget that he or she swears
will be a boon to mankind. In the second, a company or other
producer of devices that already work to a certain degree
adds some completely useless component, such as a black box,
that is said to boost efficiency by a zillion percent. Needless
to say, the new component also boosts the price.
In the static arena, for instance, there's always the
cordless wrist strap. I haven't seen any of those for a couple
of years now, but I expect they'll come back one of these
days. And in the real world, not that long ago, you could
have had your house checked for radon at a price that seemed
too good to be trueand it was.
And in Europe we have seen, and to some extent still
see, widespread concern about something called ground rays,
which are said to be a causal agent in a number of serious
illnesses, including cancer. No one has actually been able
to define what ground rays are, and these ground rays can't
be measured by any physical instrument. But some gifted people
claim they can detector measure, another misuseso-called
veins of them, using pairs of bent knitting needles. Naturally,
these same beneficent people will help you screen your house
for this evil phenomenonat considerable expense to you,
of course.
Now, I don't wish to imply that such activities are
necessarily fraudulent; indeed, I suppose some such claims
are made in good faith. Nonetheless, these inventions are
still just a lot of hocus- pocus, as the following examples
attest. In each case, the gadget described met with considerable
commercial success or aroused a good deal of public interest.
Since some of these devices are still in production, I have
refrained from using their trade names here.
One day in 1980 or thereabouts, I received a call at
the laboratory from a Mr. PN, who asked if I would be interested
in an apparatus that could eliminate static electricity.
Of course I would be. I asked what kind of static electricity
it eliminated, but PN didn't quite understand my question.
As far as he was concerned, there was only one kind: human
static electricity. So I invited him to come over and demonstrate
his device for me.
It consisted of two shoe-sole-shaped copper cutouts,
nicely chrome plated, about size 9. The two plates were connected
by an ordinary insulated wire about 150 cm long. The insulated
wire was attached to a common wire 2 to 3 m long that ended
in a ground connector, which was designed to hook onto a heating
radiator or water pipe.
There was also a nice pair of socks that went with
the setup.
PN boasted that by wearing these soles inside shoes,
the user would be drained of static electricity. (I tried
to object that someone who was grounded surely couldn't get
charged anyway, but evidently I was missing the point.) And
the claims didn't stop there: according to PN, the soles would
keep working even after the user took them off!
Not wishing to insult him, I merely said, mildly,
"Let's do an experiment." I demonstrated that just walking
across our asphalt floor caused me to become charged to about
3 kV. I then mounted the soles (hoping, as I did so, that
nobody else was watching): no charging. I removed the soles
and, once again, got charged to 3 kV.
Oh, but I hadn't worn the soles long enough, PN said;
they hadn't had time to drain the static from my body. I explained
that the charging of a person is a business between the underside
of his or her shoes and the floor covering. But no. By PN's
reckoning, human static electricity flowed in the body along
the acupuncture channels.
He had it all worked out. If you slept with these acupuncture
soles on, you slept much better, he said. If you were suffering
from one or another of various illnesses, there was a schedule
for you to follow that told you what hours of the night you
should wear the soles for best effect.
What PN wanted from me was an official statement to
use in his patent application. I told him there was nothing
there to patentnothing newand besides, I said,
his soles could be downright dangerous if someone happened
to touch a live wire while wearing them.
PN later modified his invention, severing the ground
connection and wrapping the two loose ends around a copper
core. Thus altered, it gave a reasonable decay resistance,
thanks to the semidirty surfaces of the wires' insulation.
But what was the point of the copper core? No explanation
was forthcoming.
Over the next couple of years, I had the dubious pleasure
of dealing with PN on other occasions. He managed to attract
a certain amount of public attention to his acupuncture soles,
which were written up in several newspapers and even got some
sort of endorsement from the secretary of the interior. (I
cannot help remarking that this same secretary always carried
a couple of chestnuts in his pocket, believing they were good
for his rheumatism. They apparently workedhe never had
rheumatism in his whole life.
In any event, PN kept sending me copies of his correspondence
with all of the various authorities and the institutions at
which he talked people into using his device. Of course, he
made sure to forward documentation of all the glowing praise
heaped on him when his soles won a silver medal as runner-up
for best invention of the year at a big exhibition in Brussels!
But it was a source of constant irritation to him that he
couldn't secure an official approval, and he even went so
far as to complain to the president of our university about
me, charging that I had hindered people from learning about
his brainstorm.
The president answered that I was the expert (thank
you).
By sheer chance, I learned that PN had applied for
a Danish patent and was on the verge of getting it, due mostly
to the fact that none of the patent authorities knew any more
about static electricity than did PN himself. I protested,
and eventually the patent application was denied. Naturally,
PN went to court with a civil case against our laboratory
for preventing him from winning the patent he so rightly deserved.
When asked if I wanted to appear in court, I said most
emphatically that I did not. The lawyers and judge could read
my protest, and besides, they had the wrong plaintiff. PN
should have been bringing suit not against our laboratory,
but against the laws of physics. Happily, the case was dismissed.
I don't think PN was deliberately trying to con people.
He probably honestly believed his own theories and saw himself
as the little man standing up to the men in white coats. I
spent many hours trying to teach him a little physics, but
to no avail. (Come to think of it, I've often had the same
experience with physicians.)
My last encounter with PN ended on a somewhat tragicomic
note. PN had succeeded in getting the Institute of Technology
of Denmark, an institution for technical applications, to
look at his gadget, and the institute staff pleaded with me
to come to a demonstration and put this business to rest once
and for all. I agreed to be present.
PN brought his father along to the meeting. At one
point during his demonstration (in which there was absolutely
nothing new), PN made some outrageous statement, and I could
stand it no more. "If that were the case, it would violate
Ohm's law!" I cried.
The father then interjected, "The parliament issues
new laws all the time. Couldn't it also change this Ohm's
law you're talking about?"
And now for a more suspicious story.
Over the last couple of decades there has been, at
least in Europe, a great deal of concern voiced over the static
electric field generated by monitors and television screens.
It is this field that makes dust and other particles plate
out on the screen, due to simple static attraction as well
as polarization forces.
If a person is sitting close to the screen, the field
will be distorted and will converge toward the person's face,
and the particles will then plate out on his or her nose,
forehead, and cheeks. Studies have shown that any static field
on a person's face will dramatically increase the plate-out
rate of particles, and scientists have speculated that this
may result in an increase in the occurrence of rashes and
more-serious skin diseases such as eczema, given the presence
of allergens or other unsavory substances in the air.
As far as I know, this connection has not yet been
established definitively, but many years ago we demonstrated
at our laboratory that it was possible to drastically reduce
the field put out by a monitor by applying a topical antistat
to the screen. (The antistatic layer forms a primitive but
fairly effective Faraday screen.) Later, several types of
transparent, conductive filters designed to be mounted in
front of the screen appeared on the market. Most worked reasonably
well, though they were rather expensive.
In the late 1980s, a Danish company that had been selling
such filters for some years got the opportunity to market
a new American inventionlet's call it the Field Remover.
Someone very high-up in the corporation had already signed
the necessary papers, and the gadget came with a pretty positive
report from a Scottish laboratory. But the marketing people
wanted an opinion from our university, so I agreed to test
the device.
The Field Remover kit consisted of the following:
-
A small plastic bottle containing a
clear liquid.
-
Two (conductive) suction cups
with wires ending in small plugs.
-
A plastic box (carrying the trade
name) measuring about 6 cm3, equipped with a
light diode labeled static event detector and a ground wire.
The manufacturer's instructions advised the user to
apply the liquid to the monitor screen and, if I remember
correctly, to the keyboard; mount the suction cups on the
screen and keyboard; connect the suction cups to the box;
and, connect the box to ground. The Scottish laboratory had
followed these directions and found that the field in front
of the monitor was reduced by a factor of about 50 to 100.
Performing only the first step of the prescribed procedure,
I applied the liquid to the screen and measured the field.
With no suction cups, no magic box, and no ground wire, the
field was reduced by a factor of 50 to 100. I then went through
the remaining stepsmounting the cups and all the restbut
nothing further happened, and there was no additional reduction
in the field.
I called the staff at the Danish importer and asked
them to come and witness my measurements. When they did, we
looked at each other and I suggested, "Let's break open that
magic box and see what's inside."
The box contained a cube of carbon-black-saturated
aerated plastic. When the suction-cup plugs were inserted,
they just touched the carbon-black plastic. The diode had
only one wire attached, which terminated randomly in the plastic
like the ground wire. Obviously, neither the box nor the wiring
had any real technical or scientific purpose.
I advised the marketing people, "Buy the liquid; it's
a good antistatic. You can probably sell it for $1.50 a bottle
and make a good profit." They had been planning to sell the
whole device for somewhere between $150 and $200.
As might be expected, my findings caused some problems
within the company. Management wasn't happy about the fact
that marketing had consulted an independent expert. It wasn't
necessary, the higher-ups insisted; they had been told in
the United States that this was a fantastic product, and besides,
there was always that Scottish report. The marketing people
came back to me and asked if I would write up a full report
on the test, which I did.
In the end, the company decided not to go ahead with
the Field Remover, and I got a grateful letter thanking me
for saving the marketers' jobs. I still wondered why the Scottish
laboratory had done such a sloppy job.
I also got a phone call from the device's "inventor."
He had learned of my report and was furious. I obviously didn't
know what I was talking about, he fumed before demanding to
know what my background was. I told him I had about 30 years
of university training in the field. Where, I inquired, had
he acquired his own expertise in static electricity? At first
he was rather vague, but when pressed he finally admitted
that his formal training consisted of one three-day tutorial
given in Chicago.
That was the last I heard of him, but not of his invention.
A couple of years later, I saw the Field Remover advertised
in a Swedish magazine.
Now, it would be wonderful if the examples cited above
were the only times the laws of physics have ever been either
unwittingly or deliberately misused. But in fact, such abuse
is all too common, in electrostatics as in other fields. In
sum, there will always be people who try to sell other people
a lot of nonsense, and there will always be people who are
willing to buy it.
Niels Jonassen, MS, DSc, retired from the Technical University of Denmark, where he conducted classes on static electricity. After retiring, he divided his time among the laboratory, his home, and Thailand, writing on static electricity topics and pursuing cooking classes. He passed away in 2006. .
Back to March/April Table of Contents
|
|