Magnetic Field from Leakage Current · CAP 1999 #A18
Physics · electromagnetism
Problem
A spherical capacitor is formed by two metallic and concentric spherical shells. The capacitor is then charged so that the outer shell carries a positive charge and the inner shell carries an equal but negative charge. Even if the capacitor is not connected to any circuit, the charge will eventually leak away due to the small conductivity of the material between the shells. What is the character of the magnetic field induced by this leakage current?
(a) Radially outwards from the inner shell to the outer shell.
(b) Radially inwards from the outer shell to the inner shell.
(c) Circular field lines between the shells and perpendicular to the radial direction.
(d) No magnetic field is induced.