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Homework Help: Charge to Mass Ratio difference between Electrons and Protons.

  1. Nov 19, 2008 #1
    1. In class we are discussing sub atomic particles and I approached my teacher with this question: If a electron is 2000 times smaller (roughly) than a proton, then the concentration of energy in the electron must be roughly 2000 times greater correct? She informed me that the charge to mass ratio of both the proton and electron are the same. But if this is true then how can a proton and electron when together have no charge? How could any atom with the same amount of electrons as protons have no charge?

    2. No equations but let me put before you this model. (computer equivalent since i cant draw it out as it is on my paper...)

    O <- this is the proton.
    o <- this is the electron.

    Notice that the proton is larger than the electron.
    If they both have a charge of 1, Negative 1 for the electron, positive 1 for the proton, then the concentration of energy in the much larger proton must be less, though the same amount of energy is still present, it is spread out further than the tightly packed energy of the electron. In my opinion this has to be true for a neutral charge to remain.

    3. Well I guess my attempt is the above. Note that this is not homework, but simply something that I need to know so I can sleep peacefully again.
  2. jcsd
  3. Nov 19, 2008 #2


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    This is wrong - the charge is the same but as you said the proton is roughly 2000 times heavier.

    There isn't really a concentration of energy - all you can say is that the charge:mass ratio is 2000 greater.
  4. Nov 19, 2008 #3
    Thanks for that. And I simply said concentration to clarify my thoughts a bit.
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