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Some elementary science textbooks contain subtle errors which pose barriers to understanding. "Static Electricity" is one subject which is rife with errors. Since the errors in textbooks seem to act like "viruses" which can "infect" our minds, I hope that the following discussion will act as a sort of "antivirus." (grin!) It should help those who read this webpage, and with luck my article might utilize some of the same rumor-dynamics as the viruses. These ideas might take off and spread through the elementary education population, and "immunize" large numbers of people against these particular misconceptions. So, please feel free to print this out and pass it to everyone you know! Don't miss OTHER ARTICLES
It's very misleading to concentrate on the "staticness" of the charges.
It derails our explanations, and hides many important concepts such as
charge
separation, density of imbalanced pos/neg charge, and the presence of
voltage fields surrounding the imbalanced charges. These things are
important even when the "static electricity" beings moving along.
If water was explained just as badly as "static electricity", then
most people would believe in two special kinds of water called "static
water" and "current water." Only the hydraulics expert would know that
the so-called "static
water" is really just pressurized water. They would know that "static
water" can
even flow along, since pressurized water need not remain still or
"static." In a similar way, "static electricity" has everything to
do with pressurized charge, and nothing to do with "electricity at
rest."
Here's a problem with the usual "static electricity" concept. Down inside
its atoms, everyday matter contains equal numbers of positive and negative
charges (Protons and Electrons) which are very close to each other.
Are these charges the "static electricity?" They are static and unmoving,
right? And each individual
electron and proton carries a charge of "static electricity." Shouldn't
we say
that physical matter is partly MADE out of "static electricity?" If so,
then where
are the sparks, where are the rising hair and crackling noises? There are
none, and this shows that the "staticness" is not an important factor.
Inside matter, the positive and negative charges are close together, and
so their effects cancel out. Even though matter is full of charges which
are "static", there is normally no "static electricity" to be seen.
Also, the presence of charged particles is not an important factor, since
matter is full of them, even when no "static electricity" appears.
Instead, it's the net electric charge which is important. Or put
more
simply: it is the separation between positive and negative
particles which is the basis for "static electricity." When quantities of
protons are separated from electrons by a large distance, we do get sparks
and rising hair. Call this "electric charge", not "static charge."
Whenever these opposite charges in matter are sorted out and separated
into groups of positive and negative, then we say that "static
electricity" has been generated. What does this have to do with the
charges remaining still or static? Nothing! In fact, if the charge
imbalance can be made to flow along, it will still retain all of its
unusual characteristics. It will still attract hair and lint, and cause
sparks, etc., even while it is flowing. This puts us into the ridiculous
situation of talking about "Static Electricity" ...which moves! It's
unfortunate that the term "static electricity" has become so widely
adopted as the name for the phenomena. If it had been called something
else, "charge
imbalance" for example, it wouldn't be nearly as misleading. It's easy to
think about
an imbalance which moves or stays still. But it's impossible to
visualize an unmoving substance which flows. And it's even
more unfortunate that textbooks have widely adopted the misleading
practice of stating that "static electricity is electricity which is
static and unmoving." This is a lie, and is no less a lie when many
textbooks say the same thing. Reality is not determined by majority vote.
No matter how many people agree otherwise, the Emperor's Clothes remain
missing.
What we call "Static electricity" also has another name: "high voltage."
The familiar electrostatic phenomena which occur in everyday situations
always involve voltages
above 1,000V, and ranging up to around 50,000
volts at the most. If it attracts lint or raises hair, it's definitely
over 1,000 Volts. Rub a balloon on your head, and you generate tens of
thousands of volts! This is voltage without a current. Here's a way to
think about it: pure electric current involves a current with low or zero
voltage, while pure "electrostatic" phenomena involve electrical voltages
with low or zero current. Scuff your feet on a carpet and you create a
voltage difference of many thousands of volts between your body and the
carpet. Study "static electricity" and you study voltage itself.
It would be wonderful if the term "Static electricity" could be removed
from the English language and replaced by "High Voltage Electricity." Or
possibly by "Separated Charge," or "Charge Imbalance," or "The Science
Called Electrostatics." This won't happen anytime soon, since the mistake
is too deeply ingrained in books and teachers, and in the minds of the
public. The best solution is to have everyone stay aware of this issue.
Try to avoid using the terms "Static Electricity" and "Static Charge."
And very definitely do not TEACH that "Static" and "Current" are opposite
kinds of electricity. After all, "charge imbalances" still are "charge
imbalances" even when they flow during an electric current. Also,
charge-flow and charge-imbalance can happen in the same wire at the same
time. Therefor, anyone who believes that "static" and "current" are two
types of opposite (and mutually-exclusive) electricity, will forever be
hopelessly confused about the true nature of any electrical phenomena.
For example, when adhesive tape
is placed on an insulating surface and then peeled off, both the tape and
the surface will become electrified. No friction was required. However,
if one of the materials is rough or fiberous and does not give a very
large footprint of contact area, then the process of rubbing one material
upon another can greatly increase the total contact area. Friction may
also remove thin layers of oil or oxide, exposing a more pure surface
beneath. The peeling tape does not have to be rubbed in order to generate
charge-imbalance, but the hair does need to be rubbed by the balloon. But
the rubbing is not the cause of electrification, electrification can come
about purely from contact. The term "Frictional electricity" is
misleading. I try to instead use the terms "Contact Electricity" or
"Electrification by Contact," or "separation of charge," or "creating
charge imbalance."
It's true that during "frictional electricity" or contact electrification,
it is *usually* only the negative electrons which are moved from one
surface to the other. But this transferring of electrons then results in
two areas of imbalanced charge, not one. As negative particles are pulled
away from the positive particles, the positives and negatives are no
longer near each other and are no longer are able to cancel each other.
Because of this, equal and opposite areas of imbalanced charge are always
created during the un-cancelling. For a visual demonstration of
this, see my Red/Green electricity article
And although the negative charges did the moving, this doesn't mean the
positive charges are unimportant! Before the charges were separated,
there were equal quantities of positive and negative charges present
within the materials. After the separating of the charges is
complete, the positive charges are just as important as the negative. In
one place you'll have more protons than electrons, and this place will
have an overall positive charge. In the other spot you'll have more
electrons than protons, for an overall negative charge in that region.
You've not caused
a "buildup of electrons", you've caused an imbalance, an un-cancelling, a
stretching apart, a separation of opposites which otherwise would cancel
each other. In fact, one appropriate term for static electrification is
CHARGE SEPARATION. Think for a moment: if you put the positive and
negative imbalances back
together, where does the "buildup of electrons" go? Nowhere, there was no
buildup there in the first place.
Putting the two polarities of charge back together
eliminates the imbalance and forms normal uncharged matter again.
See: What is Electricity?
Here are a few examples of errors caused by the contradictory meanings.
In fact, electrostatics is a bit more important than we commonly
assume. Contrary to popular belief, standard "electric current" circuits
are deeply connected with electrostatics. For one thing, it is the
electrostatic force that drives electric current! "Voltage" is an
electrostatic phenomena, it is electrostatic fields. Without
electrostatics, there could be no current and no electrical devices. It is
totally wrong to build a false wall between "Static" and "Current", it's
as silly as teaching that "pressure" and "movement" are two separate
types of water. "Static" and "Current" are two fields of study, not two
substances or energies. They are subject areas which were created
entirely by humans, they don't *really* exist separately in the real
world.
"Static electricity" is important in many other places besides lightning,
photocopiers, and doorknob sparks. For example, your muscles are driven
by long-chain molecules which are forced to slide across each other. This
sliding is performed by electrostatic attraction and repulsion between
parts of the molecule, and so your muscles are electrostatic motors! They
are "linear motors", as opposed to the rotary electrostatic "pop bottle"
motor found elsewhere on my website.
Another example: nerves function as tiny capacitors, with charge
pumps to electrify them, and ion gates to discharge them. Imagine a
nerve as being a long tubular "Leyden Jar" having billions of tiny
"VandeGraaff generators" scattered across its surface, and with billions
of "spark gaps" which always close in sequence as the nerve impulse
travels forward.
Another one: when Uranium atoms are hit by neutrons and their nucleii
split, the main source of released energy is the repulsion between
alike-charged positive protons in the fragments of the nucleus. Therefor,
nuclear reactors release the electrostatic energy of uranium
nucleii. A plutonium bomb is actually a "static electric" repulsion
bomb!
Another: when dissimilar materials touch, charge is separated. When
dissimilar semiconductors touch, we get "contact potential", a microscopic
electrostatic phenomenon which makes numerous devices possible: LEDs,
solar cells, thermocouples, ...and diodes, transistors, computers, radios,
television, internet, etc. Semiconductor electrostatics is essential to
modern electronics.
Another: one type of transistor in particular, the FET or "field effect
transistor", is purely an electrostatic device. Electrostatic fields
within it are used to open and close the conductive channel which
regulates current. See "Charge Detector" for some suggested experiments.
Are these sorts of transistors rare? No. Every single transistor in the
memory, CPU, and IO chips of modern PCs are FET transistors. Most of the
transistors in modern TVs and stereos are FETs. Few people realize that
"static electric" devices have taken over the electronics industry, or
that PCs are made from microscopic electrostatic components, or
that all the data in all the computers all over the world is stored
as tiny patterns of electrostatic charges.
"ATP" is the fuel which drives living things, from bacteria to humans.
One part of the 1997 Nobel prize in chemistry was awarded to the
researchers Boyer and Walker who discovered how energy is placed into ATP.
It turns out that ATP is assembled by an enzyme which is run by a tiny
rotating electrostatic motor! The "spring" in each ATP is "cocked" by a
little rotating molecular machine run by electrostatics. The reaction is
reversible, and ATP can drive the motor, changing it into an electrostatic
generator. A
typical human body contains around 10^16 of these rotary electrostatic
motors.
A big one next. The world is molecules. And molecules are atoms, and
atoms are themselves composed of positive and negative charged particles.
Atoms are held together by electrostatic attraction. If matter is made of
little dots, then the "bars" that connect all the dots together are made
of
electrostatic fields. Also, atoms are connected to each other through
chemical bonding, and chemical bonding is based upon electrostatic
attraction/repulsion forces. Without "Static Electricity" there would be
no chemistry, no living things. Without "Static Electricity", solids and
liquids would be gas, the
molecules of the gas would fall apart into atoms, and the atoms would turn
into
separate electrons and nucleii. Without electrostatics, the entire
universe would be a boring, featureless cloud of neutral-particle gas.
Some people consider electrostatics to be boring. On the contrary,
electrostatics is the thing that makes this universe an interesting place!
Franklin wrote about "drawing down the lightning" from a thunderstorm.
What he actually did was to show that a kite would collect a tiny bit of
imbalanced electric charge out of the sky during the early parts of a
thunderstorm, before lightning strikes became a danger. Feeble electric
leakage through the air caused his kite and string to become electrified,
and the hairs on the twine stood outwards. Twine is slightly conductive
on a humid day, and the twine served as Franklin's "antenna wire." The
twine was then used to electrify a metal key, and tiny sparks could then
be drawn from the key. (A metal object is needed because sparks cannot be
directly drawn from the twine. The twine is slightly conductive, but not
conductive enough to allow sparking.) No noise, no big flash, just boring
yet earthshaking science experimenting. The presence of sparks suggested
to Franklin that some stormclouds carry strong electrical charges, and it
IMPLIED that lightning was just a large electrical spark.
The common belief that Franklin easily survived a lightning strike is not just wrong, it is dangerous: it may convince kids that it's OK to duplicate the kite experiment as long as they "protect" themselves by holding a silk ribbon with a key tied in the middle. Make no mistake, Franklin's experiment was extremely dangerous. He could have been killed at any moment, and if lightning had actually hit his kite, today he would be regarded as a colonial politician who was killed by stupidity, not as a famous scientist who founded a major new research area.