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Line Integral

  1. Nov 18, 2014 #1

    ewr

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    img.png

    In the problem attached, why is the integral become just the length of line cf?
     
    Last edited: Nov 18, 2014
  2. jcsd
  3. Nov 18, 2014 #2

    Nugatory

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    Staff: Mentor

    That result pretty much follows from the definition of a line integral. If you're not familiar with that concept, google will find you some pretty decent explanations.
     
  4. Nov 18, 2014 #3

    jtbell

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    Note that in part (a) the integral becomes just the length of line if, that is, d.
    $$V_f - V_i = -\int^f_i {\vec E \cdot d\vec s}
    = -\int^f_i {E(\cos 0^\circ)ds} = -E \int^f_i {ds} = -Ed$$
     
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