Rotation of a Rigid Object about a fixed axis

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The discussion revolves around calculating the rotational speed of a wheel after a lead weight collides with it. The wheel consists of thin rods and a metal ring, with the lead weight impacting it horizontally. Participants express confusion about determining the final angular momentum (L_f) and the transition from linear to angular momentum. Suggestions include using the conservation of energy and calculating the total moment of inertia (I) to find the angular velocity (ω). The conversation emphasizes the importance of understanding the relationship between linear momentum and angular motion in this context.
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Homework Statement


A wheel is comprised of two 50.0 cm long thin rods of negligible mass and a thin metal ring with a mass of 10.00 kg, mounted on a very low friction bearing. A 100 gram lead weight is shot horizontally at the stationary wheel with an initial speed of 50.0 m/s and sticks to the rim of the wheel. What is the rotational speed of the wheel plus lead mass immediately after the collision? Give your answer in revolutions/second.


Homework Equations


L_f=(I_a + I_b)W_f



The Attempt at a Solution


I know of to find the moments of inertia I am just confused about how to find L_f. The bullet would be travelings in a linear momentum not angular. How can i find this value?
 
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I think you should just use conservation of energy.

You can get the total moment of inertia I, the equation 0.5Iω2=0.5mv2 to get ω.
 
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