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Continuous Charge Distributions

  1. Jul 6, 2014 #1
    1. The problem statement, all variables and given/known data

    A charge lies on a string that is stretched along an x axis from x = 0 to x = 3.00 m; the charge density on the string is a uniform 9.00 nC/m. Determine the magnitude of the electric field at x = 8.00 m on the x axis.

    2. Relevant equations
    [itex]
    \int_0^3 kλ/(8-x)^2\,dx
    [/itex]
    3. The attempt at a solution

    k=8.99e9
    λ=9

    I know k and λ can come out of the integral leaving 1/(8-x^2). which gives me 9.44e-10 which webassign marks wrong.
     
  2. jcsd
  3. Jul 6, 2014 #2

    vela

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    Your set-up looks fine, but I don't get anything close to the numerical answer you're getting.
     
  4. Jul 6, 2014 #3

    TSny

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    Are you thinking about the units for λ?
     
  5. Jul 6, 2014 #4
    Problem was the units for λ. Thanks for your help
     
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