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## Homework Statement

Hi all,

I need to find the potential of a positively charged rod with charge Q. Assuming to the right as positive,the center of the rod is on the origin, and it extends to -L/2 in the negative x direction, and L/2 in the positive x direction.

There is a point at distance x, located to the right of the rod, on the x axis.

I have to express the answer in terms of the variables Q, L, x, and appropriate constants.

## Homework Equations

V= ∫K*dQ/R

λ=Q/L

## The Attempt at a Solution

I know this question has been asked here before, but I wasn't able to come to a conclusion about it myself based on these posts...so here we go:

I started by choosing an arbitrary point on the rod, called dQ, that is a distance dx away from the point.

λ=dQ/dx

dQ=λ*dx

I have my equation

V=∫K*dQ/R

sub in for dQ

V=∫K*λ*dx/R

I know I need to integrate over the length of the rod. So i decided to use the bounds as 0 to L/2, and then multiply the integral by 2.

This is where I am stuck. I don't know what the value for R is...I am leaning towards x+L..but I am not sure. Also I seem to have gotten rid of my Q variable..so im not sure I should have subbed in λ*dx for it...

Any suggestions would be greatly appreciated!