Spin Angular Momentum - Bullet hitting bottom of a thin rod?

AI Thread Summary
Angular momentum is conserved in the system due to the absence of external torques, while energy is not conserved because of the inelastic collision. Linear momentum is also not conserved because an external force acts on the rod's center of mass, preventing forward motion post-collision. To solve for the final angular velocity after the bullet embeds in the rod, one should equate the initial angular momentum with the final angular momentum. The problem can be approached as a ballistic pendulum, where gravitational acceleration (g) plays a crucial role in the calculations. Understanding these principles will clarify the dynamics of the system.
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Homework Statement



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Homework Equations





The Attempt at a Solution


Angular momentum is the only parameter conserved. This is because there are no external torques acting on the system. Energy is not conserved because the collision is inelastic. Finally, linear momentum is not conserved because there is an external force acting on the rod's center of mass that prevents the system from moving forward after the collision.

Now, for part d, I am not so sure what to do. Should I equate the angular momentum of the system before the bullet hits with the final angular momentum of the system, solve for angular velocity, and turn that into linear velocity? Though I have no idea how g would come into play..
 
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Your plan to get going is good. After the embedding of the bullet, the thing is just a kind of pendulum (a variation on the ballistic pendulum).

If you fill in the relevant equations under 2, you automatically get to see the role of g.
 
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