Question regarding conservation of angular momentum

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Angular momentum is conserved in the described scenario, but it requires considering the entire system, including the disk, clay, the thrower, and the Earth. When the clay sticks to the disk, the system's total angular momentum remains constant immediately before and after the collision, despite the presence of friction. Friction affects the disk's rotation over time but does not impact the conservation of angular momentum during the instantaneous collision. The interaction between the disk and the Earth also plays a crucial role in this conservation. Thus, while friction will slow the disk, it does not negate the conservation of angular momentum at the moment of the clay's impact.
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Let's say I had a disk sitting at rest and I threw a ball of clay toward the edge of the disk, causing the clay to stick to the disc and having both rotate as a result. If the wheel's axle had friction and would eventually slow the disc down, can you still say that angular momentum is conserved just before and just after the collision (similar to impulse approximation for linear momentum)? Thanks.
 
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Sure. You just must consider a system consisting not only of your disk and blob of clay, but also of you and whole Earth, as you change Earth angular momentum as you throw, and friction transmits the momentum between disk and Earth.
 

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