Solving Spinning Animals Problem with Negligible Mass and Length

[rsala]

Homework Statement

A wooden rod of negligible mass and length 85.0 is pivoted about a horizontal axis through its center. A white rat with mass 0.500 clings to one end of the stick, and a mouse with mass 0.240 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?

Homework Equations

conservation on energy??

The Attempt at a Solution

at this moment, its not that i can't "solve" the problem, but i don't understand the situation.

when it says "is pivoted about a horizontal axis through its center."
what does it mean? does it mean that it is a stick standing straight up with animals holding on??

 

[hunter151]

I picture it like this:


Rat-------------------------------------O-------------------------------Mouse
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And it rotates around the center point.

EDIT: I guess its not showing up right, but imagine the vertical bar extending from the center of the rod.