Initially, all of the energy in the system is gravitational. Just before the rod hits the ground, all of the gravitational energy is converted to kinetic energy, assuming we use the ground as the reference level of the potential energy. The initial potential energy is given
![]() The final kinetic energy is given by ![]() where ![]() ![]() ![]() Therefore, ![]() The speed of the free end just before it strikes the ground is then ![]() Therefore, answer (C) is correct. |