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Electric field intensity for a uniformly charged wire.

  1. Jan 21, 2005 #1


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    A uniformly charged wire with a charge density of p (rho) extends along the z-axis from z = 0 to z =+ infinity. Determine the electric field intensity at a point P (rho, phi, 0)

    Ok so I wrote down the equation for electric field intensity for a uniformly charged wire ie E=k[integral of [rho(r-r')/ |r-r'|^3]dl] Oh and the integral would be from 0 to +infinty. Then I reduced the equations down to E=k*rho[integral of [dz'/(z-z' )^2]] taken from 0 to +infinty again. Now I have two questions. 1. Is what I'm doing so far right? 2. How do I do the integral again? I've been trying it for a while now and I can't seem to get a hold of my prof or my T.As so any help would be greatly appreciated.

    Oh and btw, I've seen some people post but with the nice lil math fonts and everything. How do you do that? I'm sure my post would have been so much easier to read if I had done it that way.

    Anwyas, thanks =)
  2. jcsd
  3. Jan 21, 2005 #2


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    Learn about it here in 5 seconds:


    You have to download the 2 first pdf files.

    Basically, you write {tex} {/tex} (but replace { and } by [ and ]) and write the code in between. You can click on math code in a thread to see what its code is.
  4. Jan 21, 2005 #3


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    Do not forget that the electric field intensity is vector quantity. The direction of the electric field due to a line segment dz at z is parallel to the straight line joining that point of the wire with P. You should decompose the electric fields into radial and vertical components, and add up (integrate) by components.

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