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

The word document with the problem is attached below.

2. Relevant equations

dE=kdQ/r2^{2}

Ex=Ecos∅

3. The attempt at a solution

dE=kdQ/r^{2}

E=kλ∫dy/(x^{2}+y^{2}) (integrating from y= -L/2 to L/2)

Ex=2kλ∫xdy/(x^{2}+y^{2})^{3/2}(change integration to y= 0 to L/2, multiplying expression by 2)

Let y=xtan∅

dy=x(sec∅)^{2}d∅

=2kxλ∫x(sec∅)^{2}/x^{3}(sec∅)^{3}d∅

=2kλ/x∫cos∅ d∅

=2kλ/x(sin∅)

=2kλ/x(sin(arctan(y/x)) (evaluated from y=0 to y=L/2)

=2kλ/x(y/(x^{2}+y^{2})^{1/2}(evaluated from 0->L/2)

=2kλ/x(L/2)(x^{2}+(L^{2})/4)^{1/2}

=((1.8X10^10)λL/(2x))*(1/x^{2}+(L^{2})/4)^{1/2}

This isn't the correct answer, though I don't know what actually is. I would appreciate any help or guidance!

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# Homework Help: Electric Field of a Straight Wire (now with the attachment)

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