Angular momentum of merry go round turntable

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The discussion revolves around a physics problem involving a person running on a merry-go-round, leading to the calculation of the turntable's angular velocity. The conservation of angular momentum principle is applied, where the initial angular momentum is set equal to the final angular momentum. The person is treated as a point mass, with their moment of inertia calculated using the formula mr^2. Participants are encouraged to assist in calculating the angular velocity of the turntable based on the given parameters. Understanding these concepts is crucial for solving similar physics problems effectively.
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Hi, I got this question wrong on a test and am really quite lost about it. I'd appreciate somebody running me through it.

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"Suppose a 55 kg person stands at the edge of a 6.5 m diameter merry go round turntable that is mounted on a frictionless bearing and has a moment of inertia of 1700 kg m^2. The turntable is at rest initially, but when the person begins running at a speed of 3.8 m/s (with respect to the turntable) around its edge, the turntable begins to rotate in the opposite direction. Caculate the angular velocity of the table."

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So I set up conservation of angular momentum
L_f = L_i
and
(Iw)_f = (Iw)_i

Can somebody please help me from there?
 
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I guess you'd treat the person as a point mass, so the person has moment of inertia mr^2. Can you calculate his angular velocity?
 
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