A long straight conducting rod carries a linear charge density of +2.0C/m . This rod is totally enclosed within a thin cylindrical shell of radius R, which carries a linear charge density of -2.0 C/m.
1) Construct a Gaussian cylindrical surface between the rod and the shell to derive the electric field in the inner space as a function of the distance from the center of the rod.
2) Construct a Gaussian cylindrical surface outside both the rod and the shell to calculate the electric field outside the shell.