Conservation of Angular Momentum in a Three Mass System

AI Thread Summary
The discussion focuses on the conservation of angular momentum in a three-mass system where two masses are connected by a rigid rod and a third mass collides with one of them. Before the collision, the angular momentum is calculated using the moment of inertia (I) and the initial angular velocity (w). After the collision, the new angular momentum (L') must be recalculated using the new moment of inertia (I') and the new angular velocity (w'). The center of mass (CM) of the system shifts after the collision, necessitating careful recalculation of I. The conservation of angular momentum principle remains applicable throughout the process.
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Homework Statement



Two masses M each are connected by a rigid rod of negligible mass having length a.The CM of the system is stationary in a gravity free space and the system rotates about the CM. with angular velocity w.One of the rotating masses strikes a third stationary ball of mass M which sticks to it.What is the angular momentum of the three mass system before and after collision?

Homework Equations



The Attempt at a Solution



For the collision conservation of linear momentum will be applicable.
Mv=2Mv' or,v'=v/2=wa/4. From this w' can be calculated.

Prior collision,L=Iw where I is the MI of the two mass system.

After collision, L'=I'w'

Please check if I am correct.
 
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the system will rotate about new center of mass. Check for the position of new center of mass!
 
So,we are to be careful to calculate I for the second time.
Second time, CM will be a/3 rd distance away from the mass 2M.Accordingly,I will change.

But angular velocity would be same as w'.Right?
 
There will be no linear momentum...
angular momentum will be conserved...
CM will change the position...
And if one wants to find w',one has to find I' carefully.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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