Relating moment of Inertia and pendulum oscillation

[heatherro92]

I took a picture of the question to help.

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.

 

[ehild]

T=2∏√(L/g) is valid for a mathematical pendulum (hanging point mass).
Use the formula valid for physical pendulum.
http://hyperphysics.phy-astr.gsu.edu/hbase/pendp.html

ehild

 

[heatherro92]

so am I solving for α in that equation and that's identical to the period?

 

[ehild]

No, α is the angular acceleration. The period is T.

ehild