Real Question This Time about a Merry go Round

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The discussion focuses on calculating the final angular speed of a merry-go-round after a person jumps onto it. The correct approach emphasizes the conservation of angular momentum rather than kinetic energy. The equation presented for angular momentum includes the initial momentum of the person and the merry-go-round's moment of inertia. A key point is that the angular speed must be converted from revolutions per second to radians per second for accurate calculations. The user ultimately seeks clarification on their calculations and the correct application of the angular momentum principle.
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A disk-shaped merry-go-round of radius 2.74 m and mass 168 kg rotates freely with an angular speed of 0.737 rev/s. A 51.7 kg person running tangential to the rim of the merry-go-round at 2.86 m/s jumps onto its rim and holds on. Before jumping on the merry-go-round, the person was moving in the same direction as the merry-go-round's rim. What is the final angular speed of the merry-go-round?
 
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Actually, ignore all of this...the kinetic energy is not relevant...i need to focus on angular momentum

therefore the equation should be:
rmv(child) + Iw = (i + mr^2)(w)

is this correct?
 
So, when I tried to solve this i got:

(2.74)(51.7)(2.86) + (1/2(168(2.74^2)(0.737) = [(.5(168)(2.74^2) + (51.7 x 2.74^2)] w

then i solved for w and got 0.8539 which is not correct

what am i missing?
 
In order for Iw to equal angular momentum, w must be given in standard units of radians/sec (not rev/sec).
 
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