Along wire is placed 2.0 cm directly below a rigidly mounted second wire (Fig. 19.42).

(a) Use the right-hand source and force rules to determine whether the currents in the wires should be in (1) the same or (2) the opposite direction so that the lower wire is in equilibrium. (It €œfloats.€)
(b) If the lower wire has a linear mass density 1.5 * 10-3 kg/m of and the wires carry the same current, what should be the current?