Relating moment of Inertia and pendulum oscillation

AI Thread Summary
The moment of inertia for a rod pivoted at one end is given by 1/3ML^2, while the period of oscillation for a simple pendulum is T=2∏√(L/g). The discussion focuses on relating these two concepts, emphasizing the need to use the formula for a physical pendulum rather than a mathematical one. The user expresses confusion over deriving the period from torque and angular acceleration, noting that α represents angular acceleration and is not the same as the period T. The conversation highlights the importance of understanding the differences between physical and mathematical pendulums in solving the problem.
heatherro92
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I took a picture of the question to help.

14tsihj.png


I know that the moment of inertia for a rod (at one end, not the center) is:
1/3ML^2

And I know that the period of oscillation is:
T=2∏√(L/g)

But I don't know how to relate them... I tried doing Torque=Iα=Fdcosθ and solve in terms of Time... but it wasn't becoming the equation and I had a random ω I couldn't get rid of. And I don't think I'm allowed to use the oscillation equation at all since I'm supposed to be deriving it, I'm just not sure what to do.
 
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so am I solving for α in that equation and that's identical to the period?
 
No, α is the angular acceleration. The period is T.

ehild
 

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