A wooden rod of negligible mass and length 80.0 cm is pivoted about a horizontal axis through its center. A white rat with mass 0.550 kg clings to one end of the stick, and a mouse with mass 0.170 kg clings to the other end. The system is released from rest with the rod horizontal.
If the animals can manage to hold on, what are their speeds as the rod swings through a vertical position?