A metal rod of length 19.2 cm and mass 101 g is free to slide over two parallel, horizontal metallic rails connected to a 10.0 V battery (see figure below). The battery has internal resistance of 0.100 Ω, and the rod and rails have negligible resistance. A 2.02 T magnetic field is directed perpendicular to the plane of the circuit.
(a) Find the magnetic force on the rod.
(b) Find the rod's speed after it has moved 29.4 cm, assuming negligible friction.