Asolid metal cylinder of radius a and length l, carrying charge λ per unit length, is surrounded by a thin metal cylinder with radius b and the same length. the outer cylinder carries no net charge. (a) find the charge densities per unit area at the inner and outer surfaces of the outer cylinder. (b) find the potential at the center, using radius b as the reference point. (c) how do your answers to (a) and (b) change when the outer surface is touched to a grounding wire? (e) find the electrostatic energy per unit length of the coaxial cylinders when the outer cylinder is charged by -a per unit length.