Yo-Yo Question - Rotational motion/angular momentum

AI Thread Summary
The discussion revolves around calculating the moment of inertia for a yo-yo-like solid with a uniform density, mass of 2.8 kg, and specific dimensions. The user attempts various formulas, including I = 1/2 MR^2 and combinations of the moment of inertia for different components, but finds them incorrect. They express frustration over not having the individual masses for the parts needed to solve the problem accurately. The user emphasizes that obtaining the correct moment of inertia is crucial for solving subsequent parts of the question. Assistance is sought to clarify the correct approach to determining the moment of inertia about the center of mass.
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Moment of inertia center of mass...

Homework Statement


Assume: Friction is negligible.
Given g= 9.81 m/s^2. The density of this large yo-yo like solid is uniform throughout. The yo-yo like solid has a mass of 2.8 kg. A cord is wrapped around the stem of the yo-yo like solid and attached to the ceiling. The radius of the stem is 5 m, and the radius of the disk is 6 m. Calculate the moment of inertia about the center of mass (axis of rotation). Answer in units of kg m^2.


Homework Equations



I = 1/2 M R^2


The Attempt at a Solution



I tried doing I = 1/2MR^2, which is wrong, I also thought of summing the I's of the two cylinders and the stem, but I that won't give you the I center of mass, and they don't give you the masses of the individual parts. I also tried MR^2 of the stem radius, also wrong. I also tried doing 1/2M(r^2 + R^2) which is also wrong. There are four parts to this question, but I think i can manage it as long as I get the inertia because I'm going to need it for the rest of the questions. Can anyone help me, I'm getting so frustrated with this problem!
 
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