Walker, Halliday & Resnick — Induction and Inductance: Problem 76

76 In Fig. 30-57, a long rectangular conducting loop, of width \(L\), resistance \(R\), and mass \(m\), is hung in a horizontal, uniform magnetic field \(\vec{B}\) that is directed into the page and that exists only above line \(aa\). The loop is then dropped; during its fall, it accelerates until it reaches a certain terminal speed \(v_t\). Ignoring air drag, find an expression for \(v_t\).