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). A connector slides without friction along the wires with a constant velocity `v`. Assuming the resistances of the wires, the conductor, the sliding contacts, and the self-inductance of the frame to be negligable, 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.