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Question from test?

  1. Nov 24, 2008 #1
    A point X is located equidistant from point A (q+) and B (q-) in a parallel plane.

    If the field intensity of A(q+) at point X is E, then what would the new field intensity be if point B (Q-) is added?

    A) 2E
    B) 0
    C) 1/2E
    D) 3/4 E

    I assumed the answer is 2E, since the field of the positive charge (A) plus the field of the negative charge (B) are combined, however, my friend says it's B and I'm not sure anymore. Please, help?
    Last edited: Nov 24, 2008
  2. jcsd
  3. Nov 25, 2008 #2


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    Hi Suzukigold! :smile:

    What do you mean by a parallel plane? :confused:

    Any three points are in a plane.

    Anyway, electric force is a vector field, so it obeys the law of vector addition, so you can't just add as if they were numbers. :smile:
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