Question

Can someone help me with counting potential difference in coaxial cables/cylinders. (inside ant outside)

I have electrodynamics course in uni now and I find this confusing.

Does anyone know any site where I could learn all this (calculations, examples, formulas needed, etc) or perhaps someone is willing to explain it to me? I'd really appreciate it...

I'm having a test tomorrow. I really need to learn this.

Answer 1

Sorry, no clue. Have you tried Khan Academy or CK-12/Braingenie?

Answer 2

One day to learn about coax cables from perfect strangers is one TALL order. Maybe if you could try to be bit more specific about what to expect it would help ... This is not meant to be a fob off, more just "buying time".
http://perendis.webs.com
Also, I don't get the use of the word "counting" in the post. Calculating or measuring maybe ...

Answer 3

look at this

http://www.ittc.ku.edu/~jstiles/220/handouts/Example%20The%20Electorostatic%20Fields%20of%20a%20Coaxial%20Line.pdf

if it's that, then yes, i and others can help. and that's a pretty neat layo ut of the thing

ie if it's just faffing around with vector calc and Gauss' LAw. so maybe post a sample question or summat?

but i'd add to @osprey 's note, can help revise not learn from scratch....

:-)

Answer 4

incidentally, if you are looking for a early years uni-level EM crash course / revision course, this set of playlists is very watchable and really well explained

https://www.youtube.com/user/lasseviren1/playlists

Answer 5

@IrishBoy123 Nice one shamrock

Answer 6

coax is sort of basically a CYLINDRICAL CAPACITOR and INDUCTOR (almost literally) "rolled into one", such that it has "application designed" impedances per unit length depending on its possibly use at radio frequencies.
The inner wire is separated from the outer "shield" by the dielectric, so that POSSIBLY a "static voltage" across the two would produce radial E field lines (it's symmetrical, and radial lines are symmetrical - rotate the thing and you "can't see the difference" type of argument).
The inductance may be associated with the actual length of the coax.
If you try to pass RF down the coax, then it's often modelled as passing an EM wave down and all hell can break loose.
I realise this is vague waffle, but it's a pretty vague q.
With a smile and maybe "good luck".

Answer 7

At the risk of an inquisition, I'd add that there could be a sort of "pecking order" here in elec and mag ...
couple of conducting wires at low (audio) frequencies -> coax at higher f -> waveguides at even higher f, and the "light fantastic" of optical fibres at optical frequencies. This last one may be a link in the chain of communications which allows me to waffle at this keyboard and you to read it.
It's a big, multi billion dollar/pound area

Answer 8

Thanks to both of you. I'm not completely new to this, just confused at some stuff. @IrishBoy123 , your link definitely helped

Answer 9

Enjoyed reviewing the links posted by @IrishBoy123 even though a lot of it was above my pay grade.

Answer 10

@DariusX @IrishBoy123 Does anyone know any site where I could learn all this (calculations, examples, formulas needed, etc) or perhaps someone is willing to explain it to me? I'd really appreciate it...

Probably a lot of people would fit there, though I can't speak for them. That's not the problem. The problem is the timing and the content and the specific thing to focus on.

Maybe this piece of "pseudo sagacity" (what ????) will help ... "Give yourself the TIME to TIME things". No ? thought not.

Answer 11

cheers peeps = cheeps


:-))


i think it might work!!

Answer 12

and thank you @radar for the kind comment