To maintain a constant emf, the moving rod of Fig. 20.2 must maintain a constant velocity. In

Question:

To maintain a constant emf, the moving rod of Fig. 20.2 must maintain a constant velocity. In order to maintain a constant velocity, some external force must pull it to the right.
(a) What is the magnitude of the external force required, in terms of v, B, L, and R? (See Problem 1.)
(b) At what rate does this force do work on the rod?
(c) What is the power dissipated in the resistor?
(d) Overall, is energy conserved? Explain.