1. The problem statement, all variables and given/known data 1.0 * 10^20 electrons flow through a cross section of a 2.0-mm-diameter iron wire in 5.0 s. What is the electron drift speed? 2. Relevant equations v_d = e*tao/m * E i_e = n_e * e * tao * A/m * E 3. The attempt at a solution I can't seem to get very far. I think that I need to find E, but I'm having no luck actually deriving it. Any suggestions?