A square bar with a mass of 0.830 kg and 19.3cm long (l) rests on two parallel horizontal rails that are 18.0cm apart (d) and 120.0cm long (L) as shown in the figure. (By horizontal it is meant that the rails lie in a plane perpendicular to the local gravitational field.) The bar carries a current, provided by the rails, of I=5.3 mA in the direction shown causing the bar to slide along the rails without friction. A uniform magnetic field of magnitude |B| = 0.560T is directed perpendicular to the rod and the rails.