Problem 3.301

A long straight wire carries a current $I_{0}$. At distances $a$ and $b$ from it there are two other wires, parallel to the former one, which are interconnected by a resistance $R$ (Fig. 3.87). A connector slides without friction along the wires with a constant velocity $v$ Assuming the resistances of the wires, the connector, the sliding contacts, and the self-inductance of the freme to be negligible, find: (a) the magnitude and the direction of the current induced in the connector; (b) the force required to maintain the connector's velocity constant.