Electricity and Cosmology
Isn't it strange? Here I thought that this was supposed to be a discussion about cosmology, and now we have descended to the point where
Mozina is proudly declaring his inability to understand what simple household electricity is. That's about as non-cosmological as it gets, but still, every cosmologist I ever met (and I have met quite a few) knows well the physics of electricity, even though some should not be turned loose on their household wiring.
For the unsuspecting lurkers that might try wiring up an electrical outlet over the weekend: At least one of the wires is not electrically neutral and will shock the hell out of you!
For the unsuspecting lurkers out there (or even the suspicious lurkers out there), Mozina is half right. One wire will indeed provide a significant jolt, but that wire, like the other 2, is in fact electrically neutral,
in the context of this discussion. You must all understand before we go any further that, if Michael Mozina is not the single most ignorant person you have ever encountered, he is certainly trying hard to convince you that he is that most ignorant person. Perhaps he is trying to parlay that reputation into a new "reality" program for the television market, "Nation's Most Ignorant" or "America's Got Ignorance". Could be a honey of a show. But let us now venture into the treacherous waters of science & technology, where the Mozina's of the world fear greatly to tread.
First let us define the basic words, something we must do carefully in the presence of Mozina, who commonly chooses to use personalized alternative definitions for most words, without bothering to mention it up front.
Electric charge is one of basic properties of fundamental particles, along with mass, energy, momentum, and a few others. A particle can have
negative charge,
positive charge, or
neutral charge, the latter meaning no net charge at all. Electrons carry an electrical charge of -1 unit, protons +1 unit, and neutrons 0 units, where I choose to measure charge in electron charge units, a common practice in the physical sciences.
Voltage is a measure of potential energy difference between two points in space as a result of any electromagnetic fields that are present. In the absence of all fields, the voltage between points will be zero. In the presence of an electromagnetic field, the voltage difference between points will depend on the nature of the field; whether or not it is static or dynamic, and the relative strengths of the
electric field and
magnetic field.
Now consider a wire. It consists of atoms bound together as a solid, so that the atoms remain fixed in place and do not move. However, the outermost electrons in the atoms are not fixed, and are free to move from atom to atom. Only certain materials can do this and we call them
electrically conductive. If the electrons move in the wire fairly easily, we say that the wire has
low resistance, and conversely, if the electrons have to be pushed harder to get from one atom to another, we say that the wire has
high resistance. When we apply an appropriate electromagnetic field to the wire, the electrons will feel an applied force and move in the direction defined by the field. Those moving electrons constitute the
electric current in the wire. As an aside, you note that electrons have negative charge and so one might naturally think of them as a negative current. But the standard practice in the electricity and electrical engineering fields is to assume positive current. We can blame that on
Benjamin Franklin, who was the fist to establish the labels of "positive" and "negative", but had no knowledge of what it actually was.
Finally, consider a wire with an electric current flowing through it. The current is pushed by an energy gradient that is represented to us as a
voltage. At any given moment in time, the number of elementary negative charges in the wire (electrons, either bound or mobile) and the number of elementary positive charges in the wire (protons bound to the atomic nuclei) is the same, or very nearly so. Hence the wire is
charge neutral, meaning that the sum of opposite charges is zero, or very nearly so. In this very same sense, the solar wind of electrons, protons and heavier nuclei is likewise charge neutral, carrying roughly the same number of each charge per unit volume on average. And in the very same sense the plasma of the interstellar medium and of the intergalactic medium are likewise
charge neutral, which could be synonymous with
electrically neutral, in an appropriate context (it is usually inappropriate to ignore context in the determination of the meaning of any word in practical language).
When Mozina says "electrically neutral" he obviously means that there is a net
voltage in the wire, which is not an unreasonable context. But it is the opposite context from the use of the term "electrically neutral" in plasma physics, where the reference is to charge neutrality, in the absence of specific indications to the contrary (i.e., in the absence of a contrary
context).
When we say that someone "does not know what they are talking about" that usually refers to an inability of that person to match together words and context into a meaningful whole. This is where Mozina is obviously a miserable failure. This is where we need to revisit the early exchange ...
You know, I've been burned many times in the past by *assuming* that you folks actually knew something about a specific topic. I think before I do that again, I would like to take a quick poll.
In a typical 110 volt extension cord or a box of Romex, there are three wires , a green (or bare) wire, a black wire and a white wire. Which of the these three wires (If any) is *NOT* neutral with respect to ground?
Don't be bashful. Let's hear your answer before we continue.
Your question reveals that not only do you not understand the difference between charge and current, you don't understand the difference between charge and voltage. In other words you know nothing whatsoever about electricity.
For the lurkers: all three wires are very close to electrically neutral. They will not be exactly neutral due to the build up of static charge, the capacitance of the wires (relevant if the extension cord is unpugged), and possibly some other such small effects.
The phrase "neutral with respect to ground" refers to voltage, not charge. Michael doesn't know the difference - which is much like not understanding what pressure is, come to think of it.
There are three paragraphs in Sol's post. Are you planning to read past the first?
I'm still waiting for an answer to my question. It's actually a very simple question, but I have no confidence that any of these guys can wire up an electrical outlet in their own house, let alone that they have any clue about plasma physics. I'd like to see how much they actually know about AC wiring before I get into plasma physics.
By now we should see what is happening.
Sol Invictus did in fact answer Mozina's question, and did so correctly. However, not understanding the difference between
current and
voltage, and not understanding what
electrically neutral means in the context of plasma physics, Mozina never even realized that his question had been answered. Given this, It should come as no surprise to anyone in the class of "unsuspecting lurker" or "suspicious lurker", that Mozina is considered by many as being simply incompetent, or worse.
After all we now see a conversation that has lasted over a year and a half, over 100 pages, over 4000 posts. Mozina in all that time has failed to make a single cogent argument on any point, on or off topic (and we are once again
way off topic when it comes to cosmology). I guess the elucidation of scientific context for those in the lurking audience may be the only socially redeeming aspect of this thread, and others like it.
