Halliday, Resnick & Walker — Electric Fields: Problem 51

51 The smaller of two concentric conducting shells has a uniform positive charge \(q_1\). The larger shell has a uniform negative charge \(-q_2\). Sketch the electric field lines between and outside the shells and give the direction of the external field lines as being either radially inward, radially outward, or nonexistent for these cases: (a) \(q_1 = q_2\), (b) \(q_1 > q_2\), and (c) \(q_1 < q_2\).