1. The problem statement, all variables and given/known data A long conducting cylinder bearing a charge [itex] \lambda [/itex] per unit length is oriented parallel to a grounded conducting plane of infinite extent. The axis of the cylinder is at distance [itex] x_0 [/itex] from the plane, and the radius of the cylinder is [itex] a [/itex]. Find the location of the line image, and find also the constant [itex] M [/itex] (which determines the potential of the cylinder) in terms of [itex] a [/itex] and [itex] x_0 [/itex]. 3. The attempt at a solution My instructor is giving us problems from a different book than we are using in class and there are some gaps in the material covered. That said, we haven't covered anything but point images (i.e., no "line images"). It seems to me that the location of the image would be at a distance [itex] -x_0 [/itex] on the other side of the plane by symmetry. Is this correct? And I have no idea how to find [itex] M [/itex]. Does anyone have any suggestions?