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Homework Help: Potential Difference b/t 2 points

  1. Jul 13, 2006 #1
    Ok, I've got a problem:

    The electric field in a region of space has the components Ey = Ez = 0 and Ex = (3.91 N/C)x. Point A is on the y axis at y = 2.83 m, and point B is on the x axis at x = 3.97 m. What is the potential difference VB - VA?

    I have tried integrating E (wrt x) * x from x=0..3.97 . I keep getting 81.5506, and its not the right answer. Anyhelp would be appreciated
     
  2. jcsd
  3. Jul 13, 2006 #2
    The p.d between A and B is [tex]-\int_{A}^{B}\vec{E}.d\vec{l}[/tex]. In your problem this reduces to [tex]-\int_{0}^{3.97}E_xdx[/tex]. Can you do it from here?
     
    Last edited: Jul 13, 2006
  4. Jul 13, 2006 #3

    Andrew Mason

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    Perhaps you could show how you are doing the integration. I am not sure about your expression for [itex]E_x[/itex]. Is the field [itex]\vec{E} = 3.91\hat{x}[/itex] N/C (ie. constant field of 3. 91 N/C in the x direction) or is it: [itex]\vec{E} = 3.91x\hat{x}[/itex] N/C (a linearly increasing field)?

    AM
     
  5. Jul 13, 2006 #4
    Thanks guys :)
     
  6. Jul 14, 2006 #5
    Well, tell us how you obtained your answer and answer Andrew's questions.
     
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