Moment of Inertia Help: Calculating Away from Axis

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SUMMARY

The discussion focuses on calculating the moment of inertia and total angular momentum for two disks, where one disk is rotating around the origin and the second disk is positioned a distance L away with a different angular velocity. The parallel axis theorem is essential for determining the moment of inertia of the second disk relative to the first. The total angular momentum is derived by summing the angular momentum contributions from both disks, calculated using the cross product of the center of mass and velocity, along with the spin angular momentum given by the formula Iω. Additionally, the total kinetic energy must be computed for the complete analysis.

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  • Understanding of moment of inertia and its calculation
  • Familiarity with angular momentum concepts
  • Knowledge of the parallel axis theorem
  • Basic principles of rotational dynamics
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  • Learn about calculating angular momentum for multiple rigid bodies
  • Explore the relationship between kinetic energy and angular momentum in rotational systems
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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 [itex]I \omega[/itex]. Just add these two together to find the total angular momentum about some point :)
 

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