Can a electron gun attract/repel permanent magnet?

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Discussion Overview

The discussion revolves around whether an electron gun can attract or repel a permanent magnet, exploring the interactions between electron beams and magnetic fields. Participants examine the implications of mass, force, and the nature of electron beams in relation to magnets.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants question if the small mass of electrons affects the ability of an electron gun to interact with a magnet.
  • One participant asserts that the electron beam is affected by the magnet rather than the other way around, suggesting that the magnet would not feel any significant effect from the beam.
  • Another participant mentions their experience with photo-electron guns, noting that while the steering system uses magnets to deflect the beam, the magnets do not move when the beam is activated.
  • A participant suggests that a very strong electron beam, such as that from a quasar, could potentially have a different interaction with a magnet.
  • There is a discussion about the structure of CRTs and the role of coils in deflecting the electron beam, clarifying that the beam originates from the gun and not from the coils.
  • One participant posits that on an infinitesimal scale, there may be mutual effects between the electron beam and the magnet, although these effects would be imperceptibly small.

Areas of Agreement / Disagreement

Participants express differing views on the interaction between electron beams and magnets, with no consensus reached on whether an electron gun can attract or repel a permanent magnet.

Contextual Notes

Some claims depend on the definitions of mass and force, and the discussion includes assumptions about the strength of the electron beam and its effects on magnets.

dan020350
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Can it do such a thing or are the particles too small ? If it is possible can I take the electron gun out my cry is you AA batteries?
 
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dan020350 said:
Can it do such a thing or are the particles too small ? If it is possible can I take the electron gun out my cry is you AA batteries?

Er... say that again? Especially the "... take the electron gun out my cry is you AA batteries..."

An electron beam doesn't have as much "mass" or weight as a typical magnet. If anything, the electron beam is the one that gets affected by the magnet, with very little effect on the magnet due to the electron beam.

So to answer your question: No.

Zz.
 
ZapperZ said:
Er... say that again? Especially the "... take the electron gun out my cry is you AA batteries..."

An electron beam doesn't have as much "mass" or weight as a typical magnet. If anything, the electron beam is the one that gets affected by the magnet, with very little effect on the magnet due to the electron beam.

So to answer your question: No.

Zz.
Sry. It is CRT. What about the toroid? Where the coils are wrap around a circle,!in the middle of the donut isn't that is how the electron beam begins? It repels out the magnet?

But that's for your reponse.
 
The magnet won't feel a thing.
The magnet as a whole is orders upon orders of magnitudes more massive than the electron.
 
dan020350 said:
Can it do such a thing or are the particles too small ? If it is possible can I take the electron gun out my cry is you AA batteries?

I've built a variety of photo-electron guns; the steering system used magnets to deflect the beam; the magnets didn't move when the beam was switched on and off.

If you had a really strong beam - such as the beam from a quasar - then it would be a different story.

You can calculate the magnetic field for any current:
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magcur.html

Then calculate the interaction with the magnet's magnetic field ... that provides the force:
http://en.wikipedia.org/wiki/Force_between_magnets

Then use Newton's second law of motion to determine the acceleration applied to the mass of the magnet. If it is enough to overcome the force of gravity - then it will lift the magnet.

If you solve the general problem for a simple geometry you can then calculate what is required to move a given magnet.
 
Thank you
 
dan020350 said:
Sry. It is CRT. What about the toroid? Where the coils are wrap around a circle,!in the middle of the donut isn't that is how the electron beam begins? It repels out the magnet?

But that's for your reponse.

No, the electron beam begins way back at the gun at the end of the tube where all the connection pins are
The coils that are placed further up the neck of the tube are used to deflect the electron beam so that it scans across the face of the tube as required

https://www.google.com.au/search?q=how+a+crt+works

Dave
 
Thank you my brothers
 
On an infinitesimal scale, I would think that the electron beam DOES effect the the magnet. I base this on the fact that attraction and repulsion occur to mutual entities. As the magnet attracts or repels the beam, the force appears to both. the Earth attracts the feather and vice versa. Imperceptibly small, immeasurably so, but it must be so.
 

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