Angular Momentum: Li = Lf Equation for 2 Cylinders

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SUMMARY

The discussion centers on the conservation of angular momentum for two cylinders, specifically using the equation Li = Lf. The initial angular momentum (Li) is represented as I1 * w1, where I1 is the moment of inertia of the first cylinder and w1 is its angular speed. After the second cylinder with moment of inertia I2 drops into the first, the final angular momentum (Lf) is expressed as (I1 + I2) * w2, where w2 is the common angular speed post-collision. The formula correctly reflects the conservation of angular momentum in a closed system.

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Homework Statement


A cylinder with moment inertia I1 rotates around a vertical frictionless axle with angular speed w1. A second cylinder with moment of inertia I2, drops into the first cylinder, then the the two objects have a similar angular speed of w2. What is the formula for the two cylinders with the conservation of momentum?

Homework Equations


Li = Lf

The Attempt at a Solution


Not sure if I'm right but this was my formula:
Li = Lf
I1 * w1 = ( I2 + I1 ) w2

Li = I1 * w1
Lf = ( I2 + I1 ) w2
 
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Im just learning this now, but the equation that I would think of using for this problem would be I=(1/3)ML^2. Then modify the equation to take into account the second cylinder, but anyone else feel free to correct me.
 

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