13. •• Suppose that the metal rod in Figure 20.11 is 20 cm long and is moving at a speed of 10 m/s in a magnetic field of 0.30 T and that the metal frame is covered with an insulating material. Find

(a) the magnitude of the induced emf across the rod and

(b) the current in the rod.

(c) Repeat these calculations if the wire were not covered and the total resistance of the circuit (rod plus frame) were 0.15 Ω.