How Do You Calculate Angular Velocity and Moment of Inertia?

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To calculate angular velocity and moment of inertia, it's essential to consider both rotational and translational kinetic energy, as the center of mass of the objects involved is in motion. The discussion highlights the importance of recognizing the dynamics of the system, particularly as it collapses toward the central axis of symmetry. The user seeks feedback on their calculations for moment of inertia to determine angular velocity accurately. Understanding the interplay between these forms of energy is crucial for solving the problem effectively. Accurate calculations will lead to a better grasp of the system's overall motion.
edeffect
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Hey

Just trying to work out this question (see image). Solving for I (see other image) in an effort to find the angular velocity. Could someone have a look at this working and tell what I am doing right and wrong?

Thanks Heaps

Ed
 

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There is not only going to be rotational kinetic energy, but translational KE as well. After all, the center of masses of both bars are falling and are also moving toward each other, as the system collapses toward the central axis of symmetry.
 

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