At least One Faraday Tube Between Every Two Unlike Charges in the Universe

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Discussion Overview

The discussion centers around the concept of Faraday tubes and their relation to electrostatic forces between unlike charges. Participants explore the implications of these tubes on the nature of electric fields, flux lines, and Gauss's law, addressing both theoretical and conceptual aspects of electrostatics.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that a single positive charge is connected to all negative charges in the universe via lines of forces, raising questions about the implications of this connection.
  • Another participant challenges the idea that the number of flux lines emanating from a charge can represent the number of negative charges in the universe, noting that Gauss's law provides a finite number of flux lines for a given charge.
  • It is proposed that the constant number of flux lines implies the existence of pairs of unlike charges that may be isolated from each other, resulting in zero Coulomb force between them.
  • One participant emphasizes that "lines of flux" are merely a visualization tool and not a fundamental law, arguing that the flux through an area can be non-zero even if no lines of flux are drawn through that area.
  • Another participant reiterates that Gauss's law calculates field lines as if the charge distribution is the only one in the universe, which does not imply that the Coulomb force between opposite charges is zero.
  • A later reply points out that even if there are no lines of force crossing a certain plane, the electric field or potential at that plane is still influenced by charges located elsewhere.

Areas of Agreement / Disagreement

Participants express disagreement regarding the interpretation of flux lines and their implications for electrostatic forces. There is no consensus on the fundamental nature of lines of flux or the application of Gauss's law in this context.

Contextual Notes

Participants highlight limitations in the interpretation of field lines and flux, noting that the visualization may not accurately represent the underlying physics. The discussion also touches on the assumptions inherent in applying Gauss's law to charge distributions.

Narayanan KR
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By Classic Coulomb's Law there exists negligible yet non zero force of attraction between two unlike charges in-spite of the distance.
However for electrostatic attraction to work we need at-least one Faraday Tube(Lines of Forces) between the attracting charges, does that means,
1.A single positive charge is connected to all other negative charge in the universe via Line(s) of Forces and vice versa
2. A count of number of flux lines leaving a positive charge will give number of negative charges in the universe, but such will be an Infinite number, then why Gauss's formula gives a finite number of flux lines for a given charge ?
3. With number of flux lines of a charge being constant there will be many possible pairs of unlike charges in the universe that are completely isolated from each other and have exact zero coulumb's force between them.
 
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"Lines of flux" as drawn in your diagram are a visualisation tool. They are integral curves of the field, and infinitely many of them could be drawn in principle. ##\Phi## is often casually described as the number of field lines passing through a surface, and if you draw a finite number of lines and restrict yourself to surfaces perpendicular to the electric field then it's pretty close to proportional. But it's clearly not actually a literal count of field lines because it's not dimensionless.

Flux through an area is defined as ##\Phi=\int\vec E\cdot d\vec A##. Since ##\vec E## is everywhere defined, you can construct a small area that avoids any lines of flux you have drawn, but still have a non-zero ##\Phi##.

In short, you are over-interpreting a useful visualisation and aid to intuition as a fundamental law. You might be interested in reading my Insight article on the related topic of magnetic field lines.
 
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Ibix said:
"Lines of flux" as drawn in your diagram are a visualisation tool. They are integral curves of the field, and infinitely many of them could be drawn in principle. ##\Phi## is often casually described as the number of field lines passing through a surface, and if you draw a finite number of lines and restrict yourself to surfaces perpendicular to the electric field then it's pretty close to proportional. But it's clearly not actually a literal count of field lines because it's not dimensionless.

Flux through an area is defined as ##\Phi=\int\vec E\cdot d\vec A##. Since ##\vec E## is everywhere defined, you can construct a small area that avoids any lines of flux you have drawn, but still have a non-zero ##\Phi##.

In short, you are over-interpreting a useful visualisation and aid to intuition as a fundamental law. You might be interested in reading my Insight article on the related topic of magnetic field lines.

I Read Your Insight article, I Understood Your Point, Thank You.
 
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Hard to explain where you go wrong in 1-3, in short it is what @Ibix said that you are over-interpreting the field lines tool as a fundamental law. Anyway I 'll try to state my view:

Gauss's law give us the number of field lines from a charge distribution, AS IF that charge distribution was the only one in the universe. That's why it will always give us the same number (as long as we don't change the enclosed charge distribution) regardless of what's happening in the rest of the universe.

So having in mind that, it doesn't mean that because the flux we get from Gauss's law is constant that the coulomb force between some two opposite charges in the universe is zero, and neither 2. will hold because Gauss's law simply doesn't count the field lines as you think it does. Gauss's law counts the field lines as if the enclosed charge was the only charge in the universe (ok i am repeating myself here, sorry).
 
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If (on the z axis) you have positive charges at +1 , -1 and negative charges at 2 , -2, then there are no lines of force crossing the z=0 plane.
 
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Yes, but the Electric Field E or the potential V at z= -2 (say) will be still a function of both z=1 and z=2
 

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