1. The problem statement, all variables and given/known data I am having trouble grasping why exactly displacement current and conduction current are sometimes equal to each other and sometimes are not. My textbook states that the displacement current is defined as ε0 * d(EA)/dt. That is, epsilon not times change in electric flux. I understand the derivation of this formula, but in some problems I attempt, I have to make use of the fact that displacement current = conduction current (such as, for instance, when I am told to find the displacement current density in a wire and I am only given conduction current). In other problems I have attempted, I've found different (yet correct) values of displacement current and conduction current. Thanks in advance. 2. Relevant equations Ic = Id = ε0 * d(EA)/dt.