question_answer 46)

  Find the current in the sliding rod AB (resistance = R) for the arrangement shown in Fig. 4(EP).20. B is constant and is out of the paper. Parallel wires have no resistance. is constant. Switch S is closed at time t = 0.                                      

Answer:

                  In Fig. 4(EP).23, magnetic field  is constant and is out of paper. When the sliding rod AB moves with a velocity  in the direction                                shown, induced current in AB is from A to B. As switch S is closed at time t = 0, the capacitor gets charged. If Q (t) is charge on the capacitor, then   or                      ????.(i) where A is an arbitrary constant. At t = 0, = 0  Put in (i), Differentiating w.r.t. t, we get This is the current in the sliding rod.