1. The problem statement, all variables and given/known data I am having a hard time understanding where to begin with this problem. Here it is: Consider a thin rod of length L and constant density n that lies on the x-axis with endpoints at x=0 and x=L. (i) Find a formula for the gravitational potential Φ = Φ(x) at the (variable) point P located on the positive x-axis at coordinate x>L. (ii) Find the gravitational field vector E=E(x) = -E(x)i at the point P and show that the gravitational intensity is E(x)=m/x(x-L), where m is the mass of the rod. 2. Relevant equations Total mass due to mass density μ over Volume V m=∫μ dv Potential Due to Mass Density η over Curve C Φ=∫η/r dl 3. The attempt at a solution I do not know how to start a solution because first I am confused as to which equation I would use and then second I get confused as to how I find the variables. I have done this problem with a circular disk instead of a thin rod and it was easier because I could find r but now I am lost.