totally nonsense, please consider (1) initial v (2) rotating (3)

if there is no initial velocity, the bear will not fall in the trap.

when it falls, it must stretch its legs, and struggle, then there will be rotating and vibrating, which will change the speed

most important, you cannot measure the time when it first touch the bottom, if you measure the center of the mass, then the distance will not be exactly 19.617米

not funny at all.