(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

rod -a-------|---------a on x-axis, for x>-a has -Q charge, for X<a has +Q charge, find the electric field at point (x,0) x is positive

2. Relevant equations

lambda = Q/a linear charge density dQ = (lambda)(ds)

E=KQ/r^2

3. The attempt at a solution

i make dE=kdQ/(x-s)^2

integrate kdQ/(x-s)^2 between -a and a ( i can make it 0 to a and multiply by two, symmetry)

i get the result 2KQ/a[1/x^2 - 1/(x-a)^2] for E sub-x

now if i want to find x>>a i need o somehow change [1/x^2 - 1/(x-a)^2] to the 2nd taylor expansion term but how? And is my integration correct?

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# Homework Help: Electric field of a uniformly distributed rod

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