A 44.8- child is standing on the outer edge of a merry-go-round that has moment of inertia 981 and radius 2.40 . The entire system is initially rotating at 0.180 . Find the angular velocity if the child moves to a final position 1.10 from the center of the merry-go-round.

Question

A 44.8- child is standing on the outer edge of a merry-go-round that has moment of inertia 981   and radius 2.40 . The entire system is initially rotating at 0.180 . Find the angular velocity if the child moves to a final position 1.10  from the center of the merry-go-round.

bobpursley · Answer

It can't be answered very well without units given.

conservation of momentum
Ii*wi=(If)*Wf

where If=Ii+masskid*r^2
initiall, the moment of inertia for the child is zero, because r=0

watch units on angular rotation initial...