(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A turntable has a mass of 1 kg and a radius of 0.17 m and is initially rotating freely at 78 rpm (ωi,t = 8.168 rad/s). There are no external torques acting on the system. The moment of inertia of the turntable can be approximated by that of a disk (Idisk = MR^2/2).

http://online.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?courses/phys211/oldexams/exam3/sp09/fig23.gif [Broken]

A small object, initially at rest, is dropped vertically onto the turntable and sticks to the turntable at a distance d of 0.10 m from its center as shown in the figure. When the small object is rotating with the turntable, the angular velocity of the turntable ωf,t is 72.7 rpm (7.613 rad/s). What is the mass of the small object that was dropped onto the turntable?

2. Relevant equations

3. The attempt at a solution

Here i have got everything but the angular velocity of the object when combined with the disk....

I only know the smaller radius, the higher angular velocity, but i am not sure how to get the exact value with numerical calculation...

Please Could someone help me out here to get the angular velocity of the object?

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# Homework Help: Conservation of Angular Momentum problem

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