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

AI Thread Summary
Cathode rays, composed of electrons, can travel in a bundled form despite their negative charge due to specific parameters like beam width and acceleration that minimize dispersion. While electrons do repel each other, the short travel time and distance between them during their flow prevent significant scattering. Lightning behaves similarly, as it forms a plasma path that reduces resistance, allowing the current to follow without needing a net charge. Although dispersion does occur, it is not substantial enough to disrupt the flow in practical applications. Overall, the physics of electron behavior in these contexts allows for coherent movement despite their inherent repulsion.
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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