Why Isn't the Force Around Electrons Self-Neutralizing?

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Discussion Overview

The discussion centers around the nature of forces surrounding electrons, particularly questioning why these forces do not neutralize themselves. Participants explore concepts related to electric fields, forces acting on charges, and the interactions between charged particles, with a focus on theoretical and conceptual aspects.

Discussion Character

  • Conceptual clarification
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants question the premise that electrons are surrounded by a force, suggesting that only the coulombic force from the nucleus acts on them in the context of a hydrogen atom.
  • There is a discussion about the distinction between electric fields and forces, with some participants clarifying that electric fields do not act upon themselves and that forces are exerted on charges placed within those fields.
  • One participant argues that if an electron is far from other charges, it does not move, implying that forces acting on it may already be neutralized.
  • Others emphasize that the arrows in electric field diagrams represent the potential force on a new charge rather than forces acting on existing charges.
  • Some participants assert that the forces acting on charged particles are not balanced when considering them individually, as each charge experiences the field created by the other charge.
  • There is a repeated emphasis on the idea that forces depicted in diagrams do not indicate current forces acting on existing charges but rather the forces that would act on additional charges introduced to the system.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the nature of the forces surrounding electrons or whether these forces neutralize. Multiple competing views remain regarding the interpretation of electric fields and forces acting on charges.

Contextual Notes

Some limitations in the discussion include the dependence on definitions of electric fields and forces, as well as the assumptions made about the interactions between charges in various configurations.

stmartin
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I just want to ask you something. If the electrons are surround by force around them, why that force is not neutralizing itself like on this picture.
http://img150.imageshack.us/img150/9632/untitledxm4.jpg
 
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Where did you get the idea that "electrons are surrounded by force around them..."? When you solve for the Hydrogen atom, for example, there's only ONE force, and that's the coulombic central force from the nucleus. So where are all these other forces that you are referring to?

Next time, as a hint, when you try to ask something, it would be a lot more complete if you if you also clearly cite your sources.

Zz.
 
Do I understand your question correctly if I assume that by force you mean the electrical field of the electron?

The electrical field is not a force in itself. If a charge q is placed in the field E it is affected by a force determined by F=qE. The field is caused by charges, i.e. it is radiated by positive charges and terminates in negative charges, like your illustration suggests. Thus the electrical field does not act upon itself, except that the field from a charge distribution is the superposition, i.e. the vectorial sum, of the fields caused by each individual element of charge.
 
But look at the electrical force lines. They are opposite. Make an experiment with opposite forces, you'll see that they neutralize.
 
stmartin said:
But look at the electrical force lines. They are opposite. Make an experiment with opposite forces, you'll see that they neutralize.

So? It doesn't mean it is like that ALL THE TIME!

In classical E&M, a charge CAN be in equilibrium if there are no other charge around, because it experiences no net electrostatic force. This is not E&M, it is basic mechanics.

But put another charge nearby and you don't get that anymore. So I am not sure what exactly is the problem here.

Zz.
 
stmartin said:
But look at the electrical force lines. They are opposite. Make an experiment with opposite forces, you'll see that they neutralize.

No, they don't neutralize because they represent forces acting on different objects.

More explicitly, a single arrow on your diagram represents the direction and magnitude of the electric force that the charge shown on the diagram would exert on another charge if that second charge were placed at the location of the arrow.

So in order to get two forces in opposite directions, you need to place two new charges at the locations of two properly-chosen arrows. These forces do not neutralize because they act on two different objects.

This is just like if you place two balls on the floor and you push on them in opposite directions so they roll towards each other. The forces don't neutralize in this case either.
 
jtbell said:
No, they don't neutralize because they represent forces acting on different objects.

More explicitly, a single arrow on your diagram represents the direction and magnitude of the electric force that the charge shown on the diagram would exert on another charge if that second charge were placed at the location of the arrow.

So in order to get two forces in opposite directions, you need to place two new charges at the locations of two properly-chosen arrows. These forces do not neutralize because they act on two different objects.

This is just like if you place two balls on the floor and you push on them in opposite directions so they roll towards each other. The forces don't neutralize in this case either.
Like http://img403.imageshack.us/img403/6982/untitled1or9.jpg
Man look on the picture again, the forces are opposite, acting on the electron.
 
But i think the force has already been neutralized. you see , if an electron is far from other charges, it does not move itself. why? you can think that the force act on the electron itself on opposite directions has already neutralize each other.
and i think the most important thing to accept this explanation is to accept the force (or the electric field) stay where it is, it does not get through the electron and then arrives at another side to neutrolize its counterpart,but exerts and only acts on the the electron.
 
I think the both (protons and electrons) act with their electric forces on each other.
 
  • #10
stmartin said:
Like http://img403.imageshack.us/img403/6982/untitled1or9.jpg
Man look on the picture again, the forces are opposite, acting on the electron.

But as others have told you already in this thread, the arrows are not representing forces, they are field lines...
 
  • #11
stmartin said:
Like http://img403.imageshack.us/img403/6982/untitled1or9.jpg
Man look on the picture again, the forces are opposite, acting on the electron.

In any particular diagram of the electric field produced by a given set of charges, the field arrows do not indicate the forces that currently act on those already-existing charges. They represent the electric force that would be exerted on a new charge that you add to the system.

Of course, adding a new charge to the system changes the pattern of the total electric field, but this affects only what happens to the next new charge that you add to the system.

The rule is that the electric force on a charge is determined by the net electric field produced by all the other charges in the system. You don't include the field produced by the charge in question.
 
  • #12
jtbell said:
In any particular diagram of the electric field produced by a given set of charges, the field arrows do not indicate the forces that currently act on those already-existing charges. They represent the electric force that would be exerted on a new charge that you add to the system.

Of course, adding a new charge to the system changes the pattern of the total electric field, but this affects only what happens to the next new charge that you add to the system.

The rule is that the electric force on a charge is determined by the net electric field produced by all the other charges in the system. You don't include the field produced by the charge in question.
But let's say there are 2 charged particles, like on the picture, again the forces around the electron are opposite..
 
  • #13
stmartin said:
But let's say there are 2 charged particles, like on the picture, again the forces around the electron are opposite..

Force on 1 DUE to 2 is equal to force on 2 DUE to 1. But the force on 1 due to 2 is certainly NOT balanced if you simply look at 1 alone. 1 doesn't care that 2 is there. All it cares about is that it is seeing the field due to 2. That is what is causing it to experience a net force.

The same is true for 2. It is only when you look at BOTH particles as the whole system do you not have any net external forces.

Zz.
 
  • #14
stmartin said:
But let's say there are 2 charged particles, like on the picture, again the forces around the electron are opposite..
But jtbell was talking about your latest picture, showing the combined field from two separated point charges. As he explained, the arrows show the field due to those two charges that would be experienced by a third charge brought nearby.

Note that the diagram shows the combined field created by both charges, not the force that each charge exerts on the other.
 

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