Electrons are negative, same charges repel, then what about this?

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Discussion Overview

The discussion revolves around the behavior of cathode rays and lightning, particularly focusing on the apparent contradiction of negatively charged electrons traveling in a bundle despite the principle that like charges repel. Participants explore the conditions under which this occurs, including the role of velocity, distance between electrons, and the formation of plasma in electrical arcs.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions why cathode rays, composed of negatively charged electrons, do not disperse due to repulsion, suggesting that their velocity might play a role.
  • Another participant argues that the parameters of the cathode ray setup are designed to minimize dispersion, noting that while dispersion exists, the electrons are sufficiently spaced and the travel time is short.
  • A third participant introduces the concept of plasma formation during electrical arcs, explaining that the plasma path has lower resistance, which influences the current's behavior.
  • One participant acknowledges that electrons do disperse but asserts that it is not significant enough to cause issues in the context of cathode rays.

Areas of Agreement / Disagreement

Participants express differing views on the extent of electron dispersion in cathode rays and lightning. While some acknowledge that dispersion occurs, others emphasize that it is not problematic under typical conditions. The discussion remains unresolved regarding the implications of these behaviors.

Contextual Notes

Participants mention various parameters affecting the behavior of cathode rays and lightning, but the discussion does not resolve the underlying assumptions or the specific conditions that lead to the observed phenomena.

Trojan666ru
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Cathode rays are the flow of election, since electrons are -vely charged, is it normal for the rays to travel almost in a bundle without getting dispersed due to it's repulsion?
If you say it's because of its velocity, then if you imagine each electrons, they are at almost rest to each other, then why won't they scatter?
Lightning, they too do the same, how could they travel in a bundle without getting repelled each other?
 
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Trojan666ru said:
Cathode rays are the flow of election, since electrons are -vely charged, is it normal for the rays to travel almost in a bundle without getting dispersed due to it's repulsion?
The parameters (width of the beam, current, acceleration, length, ...) are chosen in such a way that dispersion is not problematic.
If you say it's because of its velocity, then if you imagine each electrons, they are at almost rest to each other, then why won't they scatter?
Dispersion exists, but the electrons are far away from each other and the travel time is very short in typical cathode ray tubes.

Lightning, they too do the same, how could they travel in a bundle without getting repelled each other?
You don't need a net charge for lightning, the atoms where the electrons are from are still there.
 
When electricity arcs through air it forms a plasma path. The plasma path has lower resistance than regular air so the current follows it. Really big breakers actually blow air between the contacts as soon as they open to evacuate the plasma and extinguish the arc.
 
As mfb points out, they do disperse. Just not so much that it is a problem.
 

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