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Forces and Charges

  1. Jan 14, 2006 #1
    Question The separation between Na+ and Cl- ions in a molecule is 0.24nm. They are point charges of +q and -q and force of attraction between them is 4.0x10^-19N.

    a) Get the magnitude of the q
    Possible Answer: Do I just use Coloumbs law? I got 1.03x10^-14C

    b) What is the electrical field strength (in magnitude and direction) at the mid-point of the molecule?
    Possible Answer: Not sure what to do here? I'm thinking maybe its 0 but that would just be too easy.

    Thanks in advance!? :smile:
  2. jcsd
  3. Jan 14, 2006 #2

    Doc Al

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    Staff: Mentor

    I didn't check your answer, but using Coulomb's law is all you need to do.

    You just found the charges in part a, so now find the field strength. What's the field at a distance from a point charge? (Hint: the charges have opposite signs, so the fields don't cancel.)
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