Conservation of angular momentum of a uniform thin rod

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The discussion focuses on the conservation of angular momentum involving a uniform thin rod of length 0.471 m and mass 4.0 kg, which rotates about a vertical axis after being struck by a 3.0 g bullet. The bullet, traveling at an angle of 60° to the rod, lodges into the rod, resulting in an angular velocity of 6.99 rad/s post-collision. The initial calculations for the bullet's velocity were incorrect due to neglecting the bullet's contribution to the system's rotational inertia. The correct approach involves incorporating the bullet's mass into the total moment of inertia to accurately determine the bullet's velocity just before impact.

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A uniform thin rod of length 0.471 m and mass 4.0 kg can rotate freely on a frictionless horizontal plane about a vertical axis through its center. The rod is at rest when a 3.0 g bullet traveling in the horizontal plane of the rod is fired into one end of the rod. As viewed from above, the direction of the bullet's velocity makes an angle of 60° with the rod.

If the bullet lodges in the rod and the angular velocity of the rod is 6.99 rad/s immediately after the collision, what is the magnitude of the bullet's velocity just before impact?

This is a hard one. I found the inertia of the rod to be .0740024 (4.003/12)*.471^2
The angular velocity is 6.99.
.0740024 * 6.99 is the momentum = .51727

I also know that momentum is the cross product of the radius and the tangential momentum (bullet momentum). Since the radius and the momentum is perpendicular you just multiply. so (.471/2) * .003 *sin(60)*v = 6.18829e-4 * v. Then the .51727 / 6.18829e-4 = v. to find 851 m/s but this is not right, what did I do wrong?
 
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The only thing you neglected was the fact that the bullet lodges into the rod and thus adds to the rotational inertia of the system after the impact. Other than that, it looks OK.
 

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