Are two charges always in electrostatic equilibrium?

AI Thread Summary
Two equal charges exert forces on each other that are equal in magnitude but opposite in direction, resulting in a net force of zero. However, this does not imply that the charges are in electrostatic equilibrium if they are free to move, as they can still change positions. Electrostatic equilibrium is defined as a state where charges in a conductor have distributed themselves to minimize repulsive forces, leading to no further motion. In a conductor, charges can reach equilibrium, but the initial conditions of free charges do not guarantee stability. Therefore, the presence of equal forces alone is insufficient to confirm electrostatic equilibrium for free charges.
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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