[填空题]
A 4.2-m-diameter merry-go-round is rotating freely with an a lo9xi ab7r5 ,7km (tdfmvyv2)ngular soo*q+:7i vi-cxr 2)jl/piiv velocity of 0 o*:)visvx q+i7 p2ci/ irolj-.8 $rad/s$ Its total moment of inertia is 1760 $kg \cdot m^2$ Four people standing on the ground, each of mass 65 kg, suddenly step onto the edge of the merry-go-round. What is the angular velocity of the merry-go-round now? $rad/s$ What if the people were on it initially and then jumped off in a radial direction (relative to the merry-go-round)? $rad/s$