A rod of mass 0.720 kg and radius 6 cm rests on two parallel rails that are d=12 cm apart and length of rails is  L=49 cm. The rod carries a current of i=48 A in the direction shown in figure. And rolls along the rails without slipping. A uniform magnetic field of magnitude 0.240 T is directed perpendicular to the rod and the rails. If it starts from rest, what is the speed of the rod as it leaves the rails.