- #1

Eric_meyers

- 68

- 0

## Homework Statement

Two infinite parallel rods are separated a distance 2d. One carries a uniformly distributed positive charge (lambda), the other an opposite charge (-lambda) the rods are parallel to the axis and intersect the x-y plane at x=0 y = +/- d. Find the electric field for a point on the positive x axis. How does E behavor for x>>d?

## Homework Equations

E = 1/(2pi*epsilion0) * (lambda) / r

## The Attempt at a Solution

Ok, so my solution is that the r = (x^2 + d^2)^1/2 using Pythagoreans theorem from any point down the x-axis to the two rods.

I'm also guessing that the two electric fields don't cancel each other and that actually they add to one another since the difference between the two rods is 2 * lambda so if I add lambda to both rods my negative lambda goes to zero and my positive 1 lambda goes to two..

So my answer for part one was

2[1/(2pi * epsilion0) * (lambda)/(x^2 + d^2)^1/2]

and then for x >> d I just took out the d term

2[1/(2pi * epsilion0) * (lambda)/x]