Moment of Inertia Help: Calculating Away from Axis

AI Thread Summary
To calculate the moment of inertia for an object away from the axis of rotation, the parallel axis theorem is essential, especially for the second disk that is a distance L from the first. The total angular momentum can be found by summing the angular momentum of both disks, which involves calculating the cross product of each disk's center of mass with its velocity and adding the spin angular momentum, given by Iω. Additionally, determining the total kinetic energy requires considering both disks' contributions. Understanding these principles will help in accurately calculating the total angular momentum and kinetic energy. Proper application of these concepts is crucial for solving problems involving multiple rotating bodies.
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Moment of inertia help!

I have a question about moment of inertia. How do you calculate an object that is away from the axis of rotation? I am trying to figure out how to find the total angular momentum of two disks. One disk is rotating around the origin. Disk 2 is connected to disk 1 and is a distance L away and rotating at a different angular velocity. I am trying to figure out if i need to use the parallel axis theorem for disk 2 and if i can sum the two disk's angular momentum's to get the total momentum. I also need to find the total kinetic energy. any help would me much appreciated. thanks.
 
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Angular momentum is calculated in two parts; first you take the cross product of the center of mass of your object with it's velocity relative to your reference point, then you find the spin angular momentum of that object which is the angular momentum it gets from spinning about its center of mass and is calculated as I \omega. Just add these two together to find the total angular momentum about some point :)
 

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