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Ionized particle path , forces etc.

  1. Aug 17, 2013 #1
    Ok so i have a question , for the sake of the argument imagine a infinitely long conducting wire with a given positive potential.
    Now along that wire in an enclosed non conducting tube around it there is a ionized hydrogen (no electrons for the argument)

    Now when a conductor like our infinitely long wire is at a potential there are electric field lines pointing outwards from the wire which are 90 degrees to the wire or perpendicular in all directions.
    Since there is positive potential int he wire our ionized hydrogen protons are repelled from the wire , we could say the electric field from the charges on the wire is pushing against the protons and vice versa , so they tend to bend away from the wire?
    Now imagine an small insulator along the length of the wire around it , the same situation wire at a potential , protons along it's sides , insulator between them , outer tube to enclose and confine the ionized hydrogen gas.
    Now what happens when I add current to the ionized hydrogen , at both ends using electrodes ?
    Now there is a current flow because of the conducting properties of the ions , now that creates a magnetic field ,

    the question then is how does this magnetic field act in the situation , does it pushes the ions further from the wire contributing to the already existing electric field perpendicular to the wire or does it act against it ?
    Normally the magnetic field is perpendicular to the electric field but this situation is slightly different.i guess.
  2. jcsd
  3. Aug 17, 2013 #2
    The central conducting wire does not generate a magnetic field because it is held at a constant, positive potential reference to some ground?
    To create the current in they proton gas, you somehow apply a potential between two sides of the tube but not to the central conductor. In this case you are applying an electric field along the length of the central wire. You then have a current generated in the gas.
    This is essential just a Coaxial Cable where your outer conducting cylinder is a gas with ( i would guess) lower conductivity than the conducting wire in the center.
    Try Gauss's law with cylindrical symmetry around a portion of the system?
  4. Aug 17, 2013 #3
    Yes indeed you can portray it as a coaxial cable , well yes the inner wire is insulated from the ionized gas for the sake of the thought experiment , also it is at some very high potential with reference to ground , as it is used for the electric field , now the ion gas is just that a gas and normally would repel from the inner wire due to the field acting on the gas particle charge but if a current passes trough the gas the gas itself become a conductor so I was kinda interested in how the forces act in such a situation.

    Now as much as I can imagine since the inner wire is at a + potential all the way , the gas is at a cathode at one end and has an anode at the other where the current enters the gas , now not taking the magnetic field into account how the gas particles (protons) would behave at each of these ends and how in overall taking the magnetic field and electric one into account.
    The theory of those fields and forces interests me more than doing some actual numbers to tell te force values at some point along this tube.

    thanks for responding , even though I feel that some skilled members of this forums have abandoned my questions ever since
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