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Homework Help: Conservative Vector Fields

  1. Apr 28, 2010 #1
    If C is the curve given by r(t)=<1+3sin(t), 1+5sin^2(t), 1+5sin^3(t)>, 0≤t≤π/2 and F is the radial vector field F(x, y, z)=<x, y, z>, compute the work done by F on a particle moving along C.

    Work= int (F dot dr)

    If F is the potential function(?), do I integrate F with respect to each variable, then substitute the values of x, y, and z in r(t)? Would this then just be dotted into 1 since d/dt sin(t) is cos(t), which is 0 at π/2? Would my answer be something like (4^2/2)+(6^2/2)+(6^2/2)?
     
  2. jcsd
  3. Apr 28, 2010 #2

    gabbagabbahey

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    Hint: [itex]d\textbf{r}=\textbf{r}'(t)dt[/itex] :wink:
     
  4. Apr 28, 2010 #3
    So the integral is gross?
     
  5. Apr 29, 2010 #4

    gabbagabbahey

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    No, the point of my hint is that you should differentiate your position function with respect to [itex]t[/itex], and then take the dot product with the position function and finally integrate the result. You'll have something like 6 terms to integrate, but they should all be straightforward.
     
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