Are two charges always in electrostatic equilibrium?

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Discussion Overview

The discussion revolves around the concept of electrostatic equilibrium in systems of two charges, particularly focusing on whether two equal charges can be considered in equilibrium based solely on the forces they exert on each other, as described by Coulomb's law. The scope includes theoretical considerations and definitions related to electrostatics.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant suggests that since the forces on the two equal charges are equal in magnitude and opposite in direction, they may be in electrostatic equilibrium.
  • Another participant questions whether equilibrium is achieved, particularly when considering free electrons and their ability to move, implying that the presence of forces alone does not guarantee equilibrium.
  • A later reply asserts that the two charges would not be in static equilibrium if they are free to move, introducing the idea that the context (e.g., being in a conductor) may affect the state of equilibrium.
  • There is a reference to the definition of electrostatic equilibrium, which involves charges optimizing their positions to minimize repulsive forces, suggesting that the initial conditions may not suffice to determine equilibrium.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether two equal charges can be considered in electrostatic equilibrium based solely on the forces they exert on each other. Multiple competing views remain regarding the conditions necessary for equilibrium.

Contextual Notes

The discussion highlights limitations in the definitions and assumptions surrounding electrostatic equilibrium, particularly regarding the movement of charges and the specific conditions under which equilibrium is defined.

kay
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What I studied was that the force on one charge due to another equal charge in the system of two charges was, (say) F; whereas the force on the other charge due to the first charge was found out to be -F. Hence they add up to be zero. So can I say that the two equal charges are in electrostatic equilibrium or to generalise any two equal charges are in electrostatic equilibrium?
(using coulomb's law)
 
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F and -F are equal in magnitude but opposite in direction.

Does that mean an equilibrium has been obtained?
( ie do 2 free electrons separated by a distance d and having F and -F acting on them continue to be separated by distance d? )
 
256bits said:
F and -F are equal in magnitude but opposite in direction.

Does that mean an equilibrium has been obtained?
( ie do 2 free electrons separated by a distance d and having F and -F acting on them continue to be separated by distance d? )
I don't think so...
 
So the two charges would not be in static equilibrium if they are both free to move about.

What if the charges were in a conductor.
Could an electrostatic equilibrium be reached in a conductor? And where would the charges then be located?

You may want to re-visit the definition of electrostatic equilibrium, such as
Electrostatic equilibrium is the condition established by charged conductors in which the excess charge has optimally distanced itself so as to reduce the total amount of repulsive forces. Once a charged conductor has reached the state of electrostatic equilibrium, there is no further motion of charge about the surface.
from
http://www.physicsclassroom.com/Class/estatics/u8l4d.cfm

( so, from you first post, the F and -F might not be enough to designate an electrostatic equilibrium situation for the charges )
 
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