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i agree, I linked more for the similarity in experience between the gp and the author in regard their unlearning

I prefer your clarifications when considering the function of capacitors

That said, water does attract water.. the term used to describe the phenomena is cohesion

https://en.m.wikipedia.org/wiki/Cohesion_(chemistry)



Don't forget about gravity as well.

Interestingly, cohesion itself is caused by electric fields between water molecules due to their polarity (uneven distribution of charge, oxygen is electron-greedy). Much like a capacitor, separating the molecules (plates of the capacitor in the analogy) requires work which gets stored in the electric field between them.


What if the iron sphere contained an osmotic membrane?


i think you could have some fun with this idea

the op author likens voltage to pressure(o)(i) within the water analogy and your osmotic membrane(ii) functions as a sort of pressure responsive valve

i'm sure there are some mental acrobatics to describe a capacitor's relationships: Q=CV; between charge(Q), capacitance(C), and pressure..er, voltage(V) using osmotic principles in place of the capacitance variable addressing the permittivity of the dialectric(iii)

but you'd have to describe osmotic pressure while waving away incongruencies between the two concepts and i think you'd end up so deep into enervated analogies it would just be better to explain in direct language ;P

(o) http://amasci.com/miscon/voltpres.html

(i) http://amasci.com/miscon/voltage.html

(ii) https://en.wikipedia.org/wiki/Osmotic_pressure

(iii) https://en.wikipedia.org/wiki/Capacitance


Cohesion is not an inverse-square field


gp> because water does not attract other water in any way

though i was merely addressing this quote your comment confuses me both in fillip and content

from cohesion wiki(o):

Water, for example, is strongly cohesive as each molecule may make four hydrogen bonds to other water molecules in a tetrahedral configuration. This results in a relatively strong Coulomb force between molecules.

from coulomb force wiki(i):

Coulomb's law or Coulomb's inverse-square law, is a law of physics that describes force interacting between static electrically charged particles.

(o) https://en.wikipedia.org/wiki/Cohesion_(chemistry)

(i) https://en.wikipedia.org/wiki/Coulomb%27s_law


Yes I knew water attracts water, but it is not relevant to the capacitor analogy. You might as well have said water attracts water via gravity, it's just not relevant in this situation.


Gravity does have an inverse-square attraction. Though obviously it is several orders magnitude less than electromagnetism, in fact the analogy holds.




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