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This problem confuses mecan anyone give me an idea on how to do this problem

  1. Dec 24, 2004 #1
    Potential Difference Problem..Help!

    :smile: Problem: Two parallel plates having equal but opposite charges are separated by 12mm. Each plate has a surface charge density of 36.0 nC/m2. A proton is released from rest at the point near the positive plate.
    Determine: The potential difference between the plates & the energy of the proton when it reaches the negative plate.

    Thanks!...Merry Christmas! :confused:
    Last edited: Dec 24, 2004
  2. jcsd
  3. Dec 25, 2004 #2


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    Homework Helper

    I'd find the electric field first, and then use that to find the potential difference.

    Assume each plate is an infinite sheet of charge. Do you know how to calculate the electric field due to a single infinite sheet of charge? You might have derived this in class already, or your textbook might have it... Or you can derive it yourself using Gauss' law.

    Then see how the fields create by these two plates of opposite charges add together.

    Since you have the field, you should be able to find the potential difference.

    You should then be able to find the electric potential energy of the proton.

    Merry Christmas! :smile:
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