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What Is "Electricity"?
©1996 William J. Beaty
Electrical Engineer
SEE ALSO:
Scroll down: list of definitions
Scientific definition of Electricity
Famous scientists' quotations
Electricity is not Energy
What is electricity, REALLY?!
All articles here
What is electricity? This question is impossible to answer because the
word "Electricity" has several contradictory meanings. These
different meanings are incompatible, and the contradictions confuse
everyone. If you don't understand electricity, you're not alone. Even
teachers, engineers, and scientists have a
hard time
grasping the concept.
Obviously "electricity" cannot be several different things at the same
time. Unfortunately we've defined the word Electricity in a
crazy way. Because the word lacks one distinct meaning, we
can never pin down the nature of electricity. In the end we're forced to
declare that there's no such stuff as "electricity" at all! Here's a
quick example to illustrate the problem.
Do generators make electricity? To answer this
question, consider the household light bulb. Inside a lamp cord the
charges (the electrons) sit in one place and wiggle back and forth.
That's AC or alternating current. At the same time, the waves of
electromagnetic field move rapidly forward. This wave-energy does not
wiggle, instead it races along the wires as it flows from the distant
generators and into the light bulb. OK, now ask yourself this: when
"electricity" is flowing, is it called an Electric Current? Yes? If so,
then "electricity" is simply the charges already inside the wires, where
a flow of
electricity is a flow of charge. And therefore we must say that
the "electricity" sits inside the wires and vibrates back and forth.
Generators do not create any, and electricity does not flow forward
through the wires.
Next, ask
yourself if electricity is a form of energy. If it's energy, then
electricity is not the movable charges. Instead, electricity is
made of invisible electromagnetic fields, and it
doesn't wiggle back and forth within the AC cables. Instead it can
only exist in the space outside the wires, and not within the metal.
Generators do create electricity, and it races along the wires at high
speed. Yet please note that Electricity cannot do
both, it cannot be both the charges and the fields, the electrons and
the energy. So which one is really
"the electricity?" Is it the wiggling electrons within the wires? Or is
it the high-speed EM field energy? The experts unfortunately cannot agree
on a narrow
definition. The reference books give conflicting answers, so there *is*
no answer.
If someone asks whether generators make electricity, it exposes a great flaw
in the way we talk about "electricity". If we can repair this flaw,
perhaps our explanations will finally make sense.
Below are the five most common meanings of the word Electricity.
Which one do you think is right? Think about this carefully, because if
one of
these meanings is correct, all the others must be wrong! After all, no
"science term" must ever possess several conflicting definitions.
Unfortunately our dictionaries and encyclopedias contain all of these
contradictions. (Click the links to find out more about each.)
The word "Electricity:" common definitions
- 1. The scientist's
definition: "Electricity" means only one
thing:
quantities of electricity are measured in Coulombs, so
"electricity" is the electrons and protons themselves; it is the
electric
charge inside metals. All wires contain electricity all the
time, that's why they're conductors.
- Examples: CURRENT OF ELECTRICITY. QUANTITY OF ELECTRICITY. COULOMBS
OF ELECTRICITY.
-
2. The everyday definition: "Electricity" means only one thing: the
electromagnetic field energy
sent out by batteries and generators.
-
Examples: PRICE OF ELECTRICITY. KILOWATT-HOURS OF ELECTRICITY.
-
3. The grade-school definition: "Electricity" means only one thing: it
refers to the flow of
electrons, the flowing motion of electric charge. When they stop
flowing, the electricity disappears.
-
Examples: "CURRENT" ELECTRICITY. AMPERES OF ELECTRICITY.
-
4. "Electricity" means only one thing: it refers to the
amount of imbalance
between quantities of electrons and protons.
-
Example: "STATIC" ELECTRICITY. DISCHARGE OF ELECTRICITY.
-
5. "Electricity" is nothing other than the classes of phenomena
involving electric charges.
-
Examples: BIOELECTRICITY, PIEZOELECTRICITY, TRIBOELECTRICITY,
THERMOELECTRICITY, ATMOSPHERIC ELECTRICITY ...ETC.
-
6. Other
less common definitions:
- "Electricity" refers to the
flowing motion of electrical energy (electric power, Watts of electricity)
- "Electricity" really means the
electric potential or e-field (Volts of electricity)
- "Electricity" only means the
glowing nitrogen/oxygen plasma (sparks of electricity)
- "Electricity" is nothing but a
field of science (Basic Electricity, Advanced Electricity)
ELECTRICITY, n.
The power that causes all natural phenomena not known to be caused by
something else.
<grin!>
(Ambrose Bierce, The Devil's Dictionary, 1911)
If we wish to agree on a single correct definition of "electricity," which
definition should we choose? The Scientific version, number one above?
But that would mean that all of our books are wrong, since books insist
that electricity is the energy, or that electricity is the motion
of charges: the current.
Except for the CRC Handbook and the NIST SI
physics standards,
the few textbooks which do use the scientific definition are all seventy
years old, or older.
Well, maybe we don't need to choose just one definition. Could we mix
them? Could we let Electricity be an "elastic term?" Suppose we ignore
all these contradictions and instead pretend that all of the above
definitions are true. Below is the "clear" and "simple" description of
electricity which results:
Electricity is quite simple: "electricity" is just the flowing motion
of electricity! Electricity is a mysterious incomprehensible entity
which is invisible and visible, both at the same time. Also,
electricity is both a form of energy and a type of matter. Both.
Electricity is a kind of low-frequency radio wave which is made of
protons. It's a mysterious force which cannot be seen, and yet it looks
like blue-white fire that arcs across the clouds. It moves forward at the
speed of light... yet it sits and vibrates inside your AC cord without
flowing forwards at all. It's totally weightless, yet it has a small
weight. When electricity flows through a light bulb's filament, it gets
changed entirely into light. Yet not one bit of electricity is ever used
up by the light bulb, and all the electricity flows out of the filament
and back down the other wire. College textbooks are full of electricity,
yet they have no electric charge! Electricity is like sound waves, no no,
it's just like wind, no, the electricity is like the air molecules.
Electricity is like cars on a highway, no, the electricity is the speed of
the cars, no, electricity is just like "traffic waves." Electricity is a
class of phenomena ...a class of phenomena which can be stored in
batteries! If you want to measure a quantity of electricity, what units
should you use? Why Volts of electricity, of course. And also Coulombs of
electricity. And Amperes of electricity. Watts of electricity and
Joules, all at the same time. Yet "electricity" is definitely a class of
phenomena; merely a type of event. Since we can't have an amount of
an event, we can't really measure the quantity of electricity at all...
right? Right?
Heh heh.
Does my description above sound stupid and impossible? You're right. It
is. The word "electricity" has contradictory meanings, and I'm trying to
show
what happens when we accept more than one meaning. Electricity
is not both slow and fast at the same time. It
is not both visible and invisible. And electricity
isn't the flowing motion ...of electricity.
Instead, approximately ten separate things have the name
"electricity." There's no single stuff called "electricity."
electricity does not exist. Franklin, Edison, Thompson, and
millions of
science teachers should've had a long talk with Mrs. McCave before they
decided to give one single name to a large variety of independent
science concepts.
Mrs. McCave was invented by Dr. Seuss. She had twenty three sons.
She named them all "Dave."
Whenever we ask "What Is Electricity," that's just like asking Mrs. McCave
"who is dave?" How can she describe her son? There can be no answer
since the question itself is wrong. It's wrong to ask "who is Dave?"
because we're silently assuming that there's only one Dave, when actually
there
are many different people. They all just happen to be named Dave. Who
is Dave? Mrs. McCave cannot answer us until she first corrects our
misunderstanding. Dave doesn't exist. She wishes she'd given them all
separate names.
For the same reason, we'll never find a simple answer to the question
"what is electricity?" because the question itself is wrong. First we
must realize that "electricity" does not exist. There is no single
thing named "electricity." We must accept the fact that, while several
different
things do exist inside wires, people wrongly call all of them by a
single name.
So never ask "what is electricity". Instead, discard the word
"electricity" and begin using the correct names for all the separate
phenomena. Here are a few of them:
The above questions all have sensible answers. But if you ask
what is electricity?, then all of the answers you'll find will just confuse you,
and you'll never stop asking that question.
"I am reminded of the professor, who when asked the question
'What is electricity?' replied 'It all depends what you mean by 'is.'"
- A. Gilchrist, ASLIB 1972
Hrm, I find that people think that "electricity" is a single
entity (which moves like syrup while it flows along at lightspeed, which
is massless yet has mass, which is totally used up by loads while entirely
being returned to the power supply. They really believe this! They
refuse to accept that "electricity" doesn't exist.)
OK, how about the following analogy. What is a crane? Simple! A crane
is a kind of migratory waterbird which is made of steel truss, lives on
diesel fuel, frogs and small fish, is typtically hundreds of feet tall,
and is found
both in wetlands and city construction sites. Cranes are very simple to
understand. If you cannot imagine a 500ft steel waterbird striding across
the wetlands while lifting huge i-beams and eating frogs, you must not be
very smart. I'm an expert on cranes, so it cannot possibly be my own
explanation which is flawed. It must be you who simply cannot
grasp these obvious concepts.
In fact, the above "cranes" do not exist, and neither does "electricity."
Both are collections of completely separate concepts, but where we've
given them the same name. Construction cranes are not waterbirds, in the
same way that flowing energy (watts) is not flowing charge (amperes.)
If a flow of electricity is an electric current, then electricity cannot
be a form of energy. (Yet everyone wants to believe in giant steel
waterbirds, since that was what we were all taught as children. That
many books couldn't be wrong! Yet they are. There's actually two
separate things flowing along the wires, one moving fast, the other going
extremely slow, with both named "electricity." )
The physicist Richard Feynman has his own take on this. What is
Wakalixes? Talk to the experts, read the books, and you'll only become
confused. Everyone argues about the true nature of Wakalixes, and
experts give contradictory explanations. but they adamantly refuse to
agree upon a simple definition of the word, and Wakalixes lacks any narrow
scientific definition. (Feynman was complaining about K6 textbooks'
idiotic use of the word "energy," but his reasoning equally applies to
their crazy, impossible explanations of "electricity." The crane is a
simple beast, made of steel, yet covered in feathers...)
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