A boy of mass m = 50 kg running with speed v = 4 m/s jumps onto the outer edge of a merry-go-round of mass M = 150 kg and radius R = 2 m, as shown in the picture above. The merry-go-round is initially at rest, and can rotate about a frictionless pivot at its center. You may assume that the inital velocity of the boy is tangent to the edge of the merry-go round.(adsbygoogle = window.adsbygoogle || []).push({});

Treat the boy as a point particle and the merry-go-round as a uniform solid disk. What is the angular velocity of the merry-go-round after the boy has jumped onto it?

I don't know if I can do this, but I set the linear momentum of the boy equal to the angular momentum of the merry-go-round with the boy.

Basically, mv = Iw

For my moment of inertia, I used the sum of both masses and plugged my given information into ((M+m)R^2)/2. This was how I calculated moment of inertia. Then I plugged the boy's mass and his initial speed divided by my moment of inertia and tried to get omega (w). I got 0.5 exactly, but it's not correct. Any help would be appreciated.

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# Homework Help: Boy and Merry-Go-Round

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