Answer:
The final angular velocity is
Explanation:
From the question we are told that
The mass of the first disk is m
The radius of the first disk is r
The mass of second disk is M
The radius of second disk is R
The speed of rotation is w
The moment of inertia of second disk is
Since the first disk is at rest initially
The initial angular momentum would be due to the second disk and this is mathematically represented as
Now when the first disk is then dropped the angular momentum of the whole system now becomes
This above is because the formula for moment of inertia is the same for every disk
According to the law conservation of angular momentum
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