17) A rod of length L has positive charge O spread uniformly along its length. a) Determine an expression for the electric potential due to the rod at point 1, a distance d from the end of the rod, as shown below. (Assume the potential is zero at infinite distance.) b) Determine the change in potential in moving from point 1 to point 2. c) How much work would an external force do in moving a positive point charge q from point 1 to point 2? N