A block of mass 3.0 kg slides from rest down a frictionless surface from a height 0.66 m. The block collides with a uniform vertical rod of mass 4.4 kg and length 2.8 m and sticks to it. Find the angle theta that the rod and block pivot about O before momentarily coming to rest.(adsbygoogle = window.adsbygoogle || []).push({});

I've uploaded the associated picture here ~> http://www.villagephotos.com/viewpubimage.asp?id_=5655439&selected=550922

lemme just say, I have NO CLUE how to even approach his problem, but following an example in my horrible, HORRIBLE, text book, I did this:

Kf = Kinetic Energy after the inelastic collision

d = length of rod

Kf = (L^2)/2I

L = mvd

So:

Kf = ((mvd)^2)/2(md^2+(1/3)md^2) = 143943.8155

..lol..I decided to give up after that since I have No clue at all what to do with that absurdly large number.. At first I thought about dividing it by the weight of the system.. but I dont think I'd get very far in the right direction by doing that..any suggestions??

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# Homework Help: Conservation of Angular Momentum Problem

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