Angular Momentum Problem formula

[blue-steel]

Ive been trying to figure this problem for a while and I am stumped, If anyone has any ideas
Id really appreciate it - The problem deals with conservation of angular momentum
and the answer is provided but I don't know how to get there

please see the attached image of the problem>>

Thanks

 

[alphysicist]

Hi blue-steel,

Ive been trying to figure this problem for a while and I am stumped, If anyone has any ideas
Id really appreciate it - The problem deals with conservation of angular momentum

I don't think that is right; this problem deals not with the conservation of angular momentum, but with the change in angular momentum. What formula gives you the change in angular momentum of a system?

Once you have that formula, you can almost just plug in the numbers to get your answer. What do you get?

 

[blue-steel]

Hi alphaphysicist

I tried the Sum of all moments = change in angular momentum formula, it took me a while to figure out how to work with the cross products but I got the answer in the end, thanks