Calculating the electric field due to a wire of finite length

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aftershock
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Homework Statement



Suppose a uniformly charged wire starts at point 0 and rises vertically along the positive y-axis to a length L. Determine the components of the electric field Ex and Ey at point (x,0). That is, calculate [tex]\vec{}E[/tex] near one end of a long wire, in the plane perpendicular to the wire.

Homework Equations



E= KQ/R^2 with a point charge. So I'll be using integration as well.


The Attempt at a Solution



Ditching the vector for now and focusing on magnitude I have

dE = K (dQ/R^2)

[tex]\lambda[/tex]dL = dQ (where lambda is the linear charge density)

dE = k[tex]\lambda[/tex]dL/(x^2 +y^2)

pretty much can't figure out how to complete the integration...
 
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dL should be dy

you need to break the E field into components

the y component of the E field is (k*dq)/(x^2+y^2) * sin(t)
the x component of the E filed is (k*dq)/(x^2+y^2) * cos(t)

once you get there, use a U substitution and the integral should be trivial