The atom and its components

[Casio]

Hello and thank you for reading my first post on this forum.

I'm not part of any research departments or colleges etc, I'm just reading books of interest but seem to generate more questions than answers.

I'm currently reading about the atom and its components. What I think I have learned to date is this;

The atom is made up of protons, neutrons in a nucleus with orbiting electrons in shells or rings. My interest at the moment is about the nucleus and valence ring in regards to electricity.

What started all this off was that I read in a science book that voltage does not move through materials like steel etc, so that got me thinking well I've worked with electricity all my life and come to realize that electric shocks can be fatal, and have experienced a few in my life. Also having worked on electrical wiring and circuits most of my life also has lead to experiences where I have experienced the odd electrical shock here and there through touching bare wires.

Now I am to understand that voltage does not move through a conductor, so I have a piece of wire 1 metre long and put a 230V supply to one end, yet when I touch the opposite end the 230V is also present? Lets assume for this example that the wire is open circuit and totally impossible for electrons to flow through the wire, i.e. no current flow. If then the voltage is indeed the protons in the nucleus and they don't move, then what does move to permit voltage to pass to the opposite end of the wire?

[MigL]

Voltage is a form of potential energy, as such, it is not due to any kinetics or motion, but rather the configuration of the system.
Nothing actually moves through the open ended conductor of your example.
Once any part of it is at the higher potential, all of it is then at that potential.
( of course any changes to the potential are still subject to the maximum speed of information propagation c )

It is similar to bringing that open ended conductor to the top of a building.
It is now at a higher gravitational potential.
But nothing 'moves' along the conductor; the whole system is at the higher potential.
And, of course, if you drop it off the building, the conductor will trade gravitational potential for kinetic energy of motion.

Similarly if you subject a test charge to a voltage, or potential, that test charge will trade electrical potential for kinetic energy, and move.

You probably have also noted ( during your career ) that if you touch a conductor that is at a high voltage, but you don't complete the circuit, you effectively become part of the 'system' at the higher voltage, and you get no shock. This is due to the fact that Electromagnetism is a 'gauge' force and has no absolute scale. It is the reason birds can sit on a 15 000 V wire without getting fried. 

[Casio]

MigL thanks for clearing that up for me. So when the books refer to voltage as pressure, actually then voltage is not pressure. If this is also true then some of these books can be very misleading. 

[Strange]

3 hours ago, Casio said:

MigL thanks for clearing that up for me. So when the books refer to voltage as pressure, actually then voltage is not pressure. If this is also true then some of these books can be very misleading. 

It's true that many popular science articles (and even textbooks) don't always make it clear that what they are saying is a metaphor or an analogy.

In the case of pressure and voltage, the analogy is quite close. A lot of basic electrical principles are analogous to similar hydraulic ones: there is a an article here that summarises some of them: https://www.hydraulicspneumatics.com/technologies/article/21884389/hydraulicelectric-analogies-part-1

You can build "circuits" with components representing wire, resistors, capacitors, switches, etc. that use fluid flow.  (I don;t know how / if you can build the equivalent of an inductor, through).

There are a similar set of analogies in the design of acoustic systems, such as loudspeaker cabinets. You end up using familiar equations but where electriical values are replaced by the length or diameter of a tube , the stiffness of the walls etc.

[Casio]

Thanks Strange. You remind me of Dr Strange from Super Heroes on the TV 😊

[Strange]

11 minutes ago, Casio said:

Thanks Strange. You remind me of Dr Strange from Super Heroes on the TV 😊

i'm better looking, though. 😐