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I need to confirm my solution to this problem: A thin rod of length [itex]l[/itex] stands vertically on a table. The rod begins to fall, but its lower end does not slide. (a) Determine the angular velocity of the rod as a function of the angle [itex]\phi[/itex] it makes with the tabletop. (b) What is the speed of the tip of the rod just before it strikes the table.

For (a), I found the moment of inertia [itex]I[/itex] for the rod as well as the torque. Then, I equated the expression I found for the torque with [itex]\tau = I\alpha[/itex] and solved for [itex]\alpha[/itex]. Knowing [itex]\alpha[/itex], I then calculated the angular velocity [itex]\omega[/itex] from it with some calculus.

For (b), the answer would be

[tex]v = R\omega(0)[/tex]using the [itex]\omega[/itex] I found in (a).

I was going to do the problem by simplifying the rod using center of mass concepts, but it seems I can't do this with rotational motion.

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# Homework Help: Rod Falling

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