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Homework Help: Electric Field Conseptual Question

  1. Jun 14, 2006 #1
    Hey There, I am studying for my exam here coming up in two weeks and I came across a question with electric field. Now I can figure it out (E = kq/ r^2) but I was wonder which direction does it travel in? For example if the question was something like: A uranium nucleus contains x protons, what is the direction of the electric field from this nucleus? Either away from the nucleus or towards it. I know that is is away from the nucleus, but why is that? Thank you.

  2. jcsd
  3. Jun 14, 2006 #2

    It's simple, the electric field is in the direction of force experienced by a small positive test charge. Hence, if protons repel positive charges (force away from the nucleus), so it points away. Convention and definition is the reason.
    Last edited by a moderator: Apr 22, 2017
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