Can one cathode transfer electrons to multiple anodes

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Discussion Overview

The discussion revolves around the feasibility of having one cathode connected to multiple anodes within a tube filled with argon gas, particularly in the context of electron flow and plasma generation. Participants explore the implications of electrode arrangement, electric fields, and the behavior of electrons in such a setup.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants propose that electrons can flow from a single cathode to multiple anodes, but the distribution of current may not be even, with one anode potentially absorbing most of the current.
  • There is a suggestion that resistance tuning might help achieve a more even flow of electrons among the anodes.
  • One participant mentions the operation of a Cathode Ray Tube (CRT) as a relevant analogy, noting that a single cathode can emit electrons to a larger anode area, which could be divided into multiple anodes.
  • Concerns are raised about the mobility of electrons in argon gas, with questions about the voltages required to accelerate the electrons effectively.
  • Another participant highlights that the breakdown voltage in a gas depends on the distance between electrodes and suggests that multiple anodes could help mitigate issues related to long distances in a tube.
  • There is a discussion about the non-linear characteristics of plasma and the need for regulated voltage supplies to prevent one anode from monopolizing the current.
  • Some participants express uncertainty about their understanding of electricity and plasma behavior, indicating a desire for more foundational knowledge.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the best approach to managing electron flow among multiple anodes, and there are multiple competing views regarding the effectiveness of such a setup. The discussion remains unresolved with respect to the optimal configuration and control mechanisms.

Contextual Notes

Limitations include the dependence on specific voltage conditions, the influence of electric fields, and the non-linear behavior of plasma, which may complicate the understanding of current distribution among electrodes.

ahmed11
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what if i have a cathode at one end of a tube and multiple anodes through out the tube with argon gas, will electrons flow from the one cathode to multiple anodes like curves -ve1 to +ve1 and -ve1 to +ve2 and -ve1 to +ve3 or there has to be only one cathode and one anode for electrons to flow ( -ve1 to +ve1)
 
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ahmed11 said:
what if i have a cathode at one end of a tube and multiple anodes through out the tube with argon gas, will electrons flow from the one cathode to multiple anodes like curves -ve1 to +ve1 and -ve1 to +ve2 and -ve1 to +ve3 or there has to be only one cathode and one anode for electrons to flow ( -ve1 to +ve1)
Are you familiar with how a Cathode Ray Tube (CRT) works? In a CRT you have a single cathode emitting the electron beam, and a large anode area that the electron beam is swept over using magnetic deflection to paint the picture on the phosphur-coated anode. You could divide the anode area up into multiple anodes if you wanted, each with its own bias power supply with respect to the cathode voltage.

Why is your vessel filled with argon gas? That will limit the mobility of the electrons... What voltages are you wanting to use to accelerate the electrons?

http://ecomputernotes.com/images/crt_digram.gif
crt_digram.gif
 
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The elections will flow as long as you have one anode and one cathode more of either won't hurt. BUT if you have a row of anodes one further that the next. The first one will absorb most of the current and the next will get almost nothing.
You might be able to get even flow if you did some sort of resistance tuning.
This is only my best understanding I am not 100% if someone knows better please feel free
 
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ahmed11 said:
what if i have a cathode at one end of a tube and multiple anodes through out the tube with argon gas, will electrons flow from the one cathode to multiple anodes like curves -ve1 to +ve1 and -ve1 to +ve2 and -ve1 to +ve3 or there has to be only one cathode and one anode for electrons to flow ( -ve1 to +ve1)
The answer, in general is that you can have as many electrodes in the system as you want. The only caveat is that the PDs between the carious Cathodes and Anodes and the Electric Fields need to be right or one anode could hog all the current. The electrons leaving a cathode will naturally spread out and they will follow different paths unless you focus them in some way.
I, also would like some more details of the experiment with Argon gas that you are describing.
 
berkeman said:
Are you familiar with how a Cathode Ray Tube (CRT) works? In a CRT you have a single cathode emitting the electron beam, and a large anode area that the electron beam is swept over using magnetic deflection to paint the picture on the phosphur-coated anode. You could divide the anode area up into multiple anodes if you wanted, each with its own bias power supply with respect to the cathode voltage.

Why is your vessel filled with argon gas? That will limit the mobility of the electrons... What voltages are you wanting to use to accelerate the electrons?

http://ecomputernotes.com/images/crt_digram.gif
View attachment 197250
i was thinking about argon plasma in a tube and i know that breakdown voltage is all about the distance between electrodes so i was wondering if a set of anodes will help with this issue. say a tube 10 meter is to hard to establish because of the distance between electrodes but if a set of anodes is applied along the tube it will make it easier. or that what i had in mind. still not sure
 
sophiecentaur said:
The answer, in general is that you can have as many electrodes in the system as you want. The only caveat is that the PDs between the carious Cathodes and Anodes and the Electric Fields need to be right or one anode could hog all the current. The electrons leaving a cathode will naturally spread out and they will follow different paths unless you focus them in some way.
I, also would like some more details of the experiment with Argon gas that you are describing.
i'm not going to do the experiment i was just thinking about plasma and been reading a lot lately and wanted to know if the breakdown voltage of the gas usually depends on pressure and distance between electrodes so i was thinking this could help with the distance problem. but as you explained that one anode could take all the electrons, how to control that issue. i have very little knowledge with electricity
 
ahmed11 said:
i have very little knowledge with electricity
This topic is quite a sophisticated one and I think it would be better if you learned some before leaping in here. The problem with plasma is that it is non-linear (V;I characteristic); the more the current, the lower the resistance (not like metals which get higher resistance as the current increases and the temperature rises. To avoid one anode stealing all the current is could be necessary to supply it with a regulated supply voltage, in order to control the current it takes.
A conventional flourescent tube will not strike without help. It uses a thermionic filament at each end which produces a cloud of electrons. There are attracted to the electrode the other end and produce ionisation on the way there in an avalanche effect and the long arc becomes established in a very short time. The 'heaters' are then switched off to prolong their life.
 
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