1. The problem statement, all variables and given/known data Show that the conduction and displacement currents cancel each other for a spherical radioactive solid emitting charged particles radially outwards 2. Relevant equations Maxwell's equations Current density (j) Displacement current density (jd) 3. The attempt at a solution I haven't made it very far into the problem. I think "the conduction" means i=dq/dt and "displacement current" id=jd*S with jd= ∂D/∂t. However, I am still struggling to understand the problem.