Angular momentum problem (ball sticking to one end of a see saw)

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SUMMARY

The discussion centers on a physics problem involving angular momentum, where a 4.80 kg ball is dropped from a height of 15.0 m onto one end of a uniform bar with a mass of 7.00 kg and a length of 8.60 m. The ball sticks to the bar upon collision, prompting the need to apply conservation of angular momentum. The participant attempts to calculate the initial velocity using kinetic and potential energy equations and seeks to determine the moment of inertia (I) of the system to find the angular velocity (ω) and the subsequent height the ball rises to after the collision.

PREREQUISITES
  • Understanding of angular momentum conservation principles
  • Familiarity with moment of inertia calculations
  • Knowledge of kinetic and potential energy equations
  • Basic grasp of rotational motion concepts
NEXT STEPS
  • Calculate the moment of inertia (I) for the combined system of the bar and the attached ball
  • Learn how to derive angular velocity (ω) from angular momentum conservation
  • Explore energy conservation principles to determine the maximum height reached by the ball
  • Review examples of similar problems involving collisions and rotational dynamics
USEFUL FOR

Students studying physics, particularly those focusing on mechanics and angular momentum, as well as educators looking for practical examples of conservation laws in action.

Storm Butler
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Homework Statement



A 4.80 ball is dropped from a height of 15.0 above one end of a uniform bar that pivots at its center. The bar has mass 7.00 and is 8.60 in length. At the other end of the bar sits another 5.40 ball, unattached to the bar. The dropped ball sticks to the bar after the collision.

Homework Equations





The Attempt at a Solution


my attempt at doing this was to conserve angular momentum. so it is initially mvr where r is half of the length of the rod and v is the velocity found by equating kinetic energy with potential energy. then i set this equal to Iw of the final system but i don't know how to find I of this. I figured once i had I i could find w and set v of ball to wr and then use conservation of energy again to find the height the ball rose.
 
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