Two small spheres A and B, each of mass m, are attached at either end of a stiff light rod...

Two small spheres A and B, each of mass m, are attached at either end of a stiff light rod of length d. The system is released from rest in the position shown. Determine the speed of the spheres when A has reached point D, and determine the normal force between sphere A and the surface on which it is sliding immediately before it reaches point D. Neglect friction, treat the spheres as particles (assume that their diameter is negligible), and neglect the mass of the rod.

Figure P4.58