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

Infinite unknown line charges of 5nC/m lie along the (positive and negative) x and y axes in free space. FindEat P(0,0,4)

2. Relevant equations

E= (pl/2(pi)(eo)p)ap

pi = 3.14...

eo - permitivity of free space 8.854 x 10^-12

pl = line charge density

ap = unit vector

3. The attempt at a solution

really just need to know how to solve for the unit vectorplthen I can do the rest.

I was thinking along the lines ofap= (z-4)az/ sqrt((z-4)^2) then plug in z... not really sure. Any help would be appreciated.

The answer is 45azbut how?

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: E Field of a line charge

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