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Can Hydrogen have a DC Circuit?

  1. Aug 30, 2004 #1
    [SOLVED] Can Hydrogen have a DC Circuit?

    I'm thinking of the hydrogen atom like it might be a DC type of electrical circuit, just for fun, but I am not sure what values to use for a couple of simple equations. Can somebody help me out?

    The equation is V=I*R

    I found an impedance value, Z, in NIST's list of constants and stuff, a factor they call "Characteristic Impedance of the Vacuum". That Z value = 376.73 ohms. Can I use that as R?

    I know the BE for the H 1s electron is 13.06 eV, and it looks like I can use it for V, but I'm not sure since it has units of "eV". Can I use it for "V" as it is or do I have to change it or do something else?

    Maybe I can use the charge, Q, of the electron and calculate "V" from capcitance "C" using C = Q/V, but I have the same units problem.

    Thanks for any help!
    Hey, maybe I can use this for a science project!
     
  2. jcsd
  3. Aug 30, 2004 #2

    chroot

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    The electron-volt is a unit of energy. The volt is a unit of electrical potential. The electron volt is the amount of kinetic energy gained by electron when moved through a potential of one volt. They are not interchangeable.

    Besides, the entire premise of what you're trying to do is speculative. There is no "DC circuit" inside a hydrogen atom in any respect whatsoever.

    - Warren
     
  4. Aug 30, 2004 #3
    The number 1 problem you won't be able to get around is the fact that a hydrogen atom doesn't use energy over time, while a DC circuit needs some continuously.
     
  5. Aug 30, 2004 #4

    ZapperZ

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    The number 2 problem is that Ohm's Law is based on the Drude model of FREE electron gas in a conductor. How is this anywhere similar to a hydrogen atom?

    Zz.
     
  6. Aug 30, 2004 #5
    Bummer! I was kinda hoping that I could get some kinda number even though it might not be a real number. Are you guys really sure that I can't get even a Voltage number?
     
  7. Aug 30, 2004 #6

    ZapperZ

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    Look, the reason why physics is called PHYSICS and not MATHEMATICS is because the quantity and numbers we obtain have PHYSICAL MEANINGS. You can crank out any numbers and equations that you want out of your imagination, but it doesn't mean any of these have any physical significance. If you can't show any physical significance of a number that you crank out, or why such model is valid, then any result that you arrive at is meaningless.

    Zz.
     
  8. Aug 31, 2004 #7
    I understand. You said when an electron moves through a potential of one volt it then has one electron volt of energy. Right?

    When a free electron flies toward a free proton, does the electron develop potential as it flies closer and closer to the proton? If so do you have an idea or a number for the potential when the electron is 0.53 Ang away from the proton? Can I think of that as a short burst of electrical current?
    Thanks!
     
  9. Aug 31, 2004 #8
    Is Ohm's law involved in controlling, understanding or predicting how free electrons fly around a synchrotron loop?

    If so, then it seems that the electron, in its particle form, imitates the electron beam in the synchrotron because that one electron flies around the proton of hydrogen such that the center of the synchrotron serves as the proton. What do you think of this perspective?
     
  10. Aug 31, 2004 #9

    chroot

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    The beam path in a synchrotron is nothing at all like an electron in an orbital in an atom. Electrons do not "orbit" nuclei. Atoms are quantum-mechanical systems, while synchrotrons are not.

    - Warren
     
  11. Aug 31, 2004 #10
    yet QM-processes occur in synchrotrons

    regards
    marlon
     
  12. Aug 31, 2004 #11

    ZapperZ

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    While that is technically true, it isn't what is used in the majority of the dynamical description of a synchrotron. Classical E&M is alive and well in terms of beam physics, and the same can be said for describing the electron beam in a synchrotron. So Chroot is correct in saying that a synchrotron is a "classical" system.

    Zz.
     
  13. Aug 31, 2004 #12
    Did I get skipped?
    I liked the answer given to What are electrons, but didn't see anything about my question. Can you give me a hint? Thanks!
     
  14. Aug 31, 2004 #13
    The nucleus is understood to have a shell structure with orbits that imitate the shell structure of the electrons. Are the neutrons and protons delocalized like the electron clouds and as a result do not "orbit" or move around inside the nucleus in a structured manner? This implies that the nucleus should also be a cloud like system. This arrangement would suggest that there is there is a great deal of spherical symmetry within the nucleus.

    What is it that tells us that electrons do not orbit?
     
    Last edited by a moderator: Aug 31, 2004
  15. Aug 31, 2004 #14

    ZapperZ

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    I am guessing that you either haven't studied E&M much, or if you did, you haven't fully understood it yet.

    1. An electron going through a potential difference of X Volts will GAIN an kinetic energy equal to X eV.

    2. The proton in "electron develop potential as it flies closer and closer to the proton" is IRRELEVANT. All that proton does is to be the SOURCE of the electrostatic potential field that the electron sees, the SAME potential that is in #1. When you have the potential field due to that proton, then you can ignore that proton and simply deal with the resulting field. This field is what is causing ALL the relevant interaction on that electron.

    3. For a finite, bound charge, by definition, the zero value of the electrostatic potential is at infinity from the source charge. So all the electrostatic potential values are "calibrated" from this zero value. You can then calculate ALL the necessary energy gain or loss by that electron at ALL locations to your heart's content once you know this and #2.

    4. Useful websites such as Hyperphysics has the electrostatic potential field for point and spherical sources.

    Zz.
     
  16. Aug 31, 2004 #15
    How about the fact that, in its rest state, the electron has no angular momentum? Seems hard to describe it as an "orbit" with no angular momentum...
     
  17. Aug 31, 2004 #16

    Indeed, but relativistic and QM-notions are also to be taken into account when looking for a complete description of the synchrotron and what it does.

    regards
    marlon
     
  18. Aug 31, 2004 #17

    ZapperZ

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    Relativistic, yes. It takes no effort to get a bunch of electrons to the relativistic regime. But where exactly would "QM-notions" come in?

    Zz.
     
  19. Aug 31, 2004 #18

    Well, when an incident particle at high speed interacts with an atomic nucleus, don't we need QM (or QFT) in order to describe what happens. I mean fission and fusion are processes where the QM-regime can be applied, not ?

    Maybe I am looking at this to much in terms of the theory-aspect. I am thinking of processes like fission described in terms of the strong-force mediating pions intechanged between hadrons.

    Please, let me know if I am exagerating...

    regards
    marlon
     
  20. Aug 31, 2004 #19

    ZapperZ

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    Humm... I could have sworn that we are talking about a "synchrotron" here.

    A synchrotron is an electron storage ring. The APS here at Argonne has a ring with a circumference of almost 3/4 of a mile. In it, bunches of electrons just go round and round and round and round..... There are no collisions with anything. In fact, collision is BAD! We don't want them since it will degrades the beam quality.

    It is this that I insisted that classical physics is alive and well, and that there are no QM effects that are significant enough that QM description has to be used.

    Zz.
     
  21. Aug 31, 2004 #20
    Ok, humm, in the case of the synchrotron, you are right. I know this what we were initially talking about.

    The remarks I made concerning QM and special relativity where made as a remark to high-energy-collisions and more generally high-energy-physiscs.

    Sorry, i must have confused You.


    regards
    marlon
     
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