If the animals can manage to hold on, what are their speeds as the rod swings through a vertical position?

Question

Take free fall acceleration to be = 9.80 .
A wooden rod of negligible mass and length 75.0 is pivoted about a horizontal axis through its center. A white rat with mass 0.480 clings to one end of the stick, and a mouse with mass 0.200 clings to the other end. The system is released from rest with the rod horizontal.

Answer 1

This is easily solved using conservation of energy

.5*0.680*v^2=9.81*.375*0.280

solve for v
(was that 75.0 m or 75.0 cm for the length?) I used 75.0 cm

1.74 m/s

j