Electric energies between 2 pt charges

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Discussion Overview

The discussion revolves around the behavior of electric charges, specifically the interaction between two point charges, +2Q and -Q, when they are brought into contact and the subsequent charge redistribution. Participants explore the timing and conditions under which attraction and repulsion occur, as well as the implications of charge conduction.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant suggests that when the two point charges are brought into contact, conduction occurs, leading to a redistribution of charges until both charges reach +Q/2, at which point they repel each other.
  • Another participant clarifies that conduction is a process aimed at equalizing electric potential, which continues until the potentials are equal.
  • A different viewpoint emphasizes that while one charge is positive and the other negative, attraction occurs. Once the initially negative charge reaches zero and starts accumulating positive charge, repulsion begins.
  • One participant argues that upon contact, the charges redistribute, and when they reach 0 and +Q, there is no attraction since both charges are no longer opposite, leading to a question about the timing of repulsion.
  • Another participant states that after reaching a state of 0 and +Q, further charge flow results in both charges becoming positive, leading to repulsion.

Areas of Agreement / Disagreement

Participants express differing views on the timing and nature of charge redistribution and the conditions under which attraction and repulsion occur. There is no consensus on the exact mechanics of the process.

Contextual Notes

The discussion involves hypothetical scenarios and assumptions about point charges and their behavior during conduction, which may not account for all physical realities, such as the effects of the conducting medium.

kimchi
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+2Q and -Q two pt charges are r apart. AS no external agent exists, they attract to each other and each gains +Q/2 after conduction. Like charges repel. At same distance at r, 2*k(2Q)(-Q)/r = 2*k(Q/2)sq /r + 2 KE...
but what i want to know is that when is the like charges repel...just after a -Q of electrons flow from -Q to 2Q they repel...does conduction happen in a very short time to share equal charge of Q/2 before repulsion?? Or just just after a -Q of electrons flow from -Q to 2Q they repel?
 
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That "conduction" is nothing but an electric charge transport process whose main purpose is to equate the electric potential.It happens till the potentials are equal.

Daniel.
 
As I understand what you are saying, there are two point charges separated by a distance r. Some mechanism such as a very thin wire provides a path for charge to flow from one point to the second point. The initial charge configuration has -Q at one point and +2Q at the other. A current will flow from one point to the other until there are equal charges of +Q/2 at both points.

As long as one point is positve and the other is negative, there will be attraction. When the charge at the initially negative point is zero, there will be no attraction. As soon as the intially negative point starts accumulating net positive charge there will be repulsion. All of this neglects any charge remaining in the conducting mechanism (wire) that allows the charge to redistribute.

It is of course a hypothetical problem, but it is very important that the charges are point charges. If the charges were distributed on the surface of sphere, for example, When one shere is neutral and the other has charge Q there would be attraction because the charge on the neutral sphere (or on the positive sphere) would not be uniformly distributed. Negative charges would be attracted to and get closer to the positive sphere, resulting in an attraction between the sheres
 
No OlderDan. You misunderstood me a bit. My view is that when two point charges separated by a distance r attracts each other spontaneously. When they contact, redistribution of charges begins. Electrons flow from Point charge of -Q to Point charge of +2Q, and when it flows -Q to point charge of +2Q, they become 0 and +Q respectively. At that time, there is no attraction between the 2 new pt charges as they are not of opposite charges. Also as they at point charges of no volume or surface, no induced charges on the neutral one.
Then, how could we said when 2 original pt charges make contact, each on then carry same charges before repulsion?
 
just after state of 0 and +Q for the two charges, further flow of charges make them same kind of charge (+charge), repulsion separates them. And no more flow of charge between them happens ><
 

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