1. The problem statement, all variables and given/known data 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. 2. Relevant equations V= ∫K*dQ/R λ=Q/L 3. 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!