Determine period for off center disk

[boardaddict]

Homework Statement

A disk of mass m and radius a is suspended horizontally by a rod bored through the disk at a location d distance from the center. When in equilibrium the center of the disk is directly below the rod. Obtain an approximate expression for the period, ignore disapative effects

Homework Equations

per Newtonian

I = 1/2 mr^2 + md^2
I*theta: = -mg(rsin(theta))

The Attempt at a Solution

1/2 ma^2 +md^2

Im missing something simple here...If someone could point me in the right direction it would be appreciated

 

[boardaddict]

Homework Statement

A disk of mass m and radius a is suspended horizontally by a rod bored through the disk at a location d distance from the center. When in equilibrium the center of the disk is directly below the rod. Obtain an approximate expression for the period, ignore disapative effects

Homework Equations

per Newtonian

I = 1/2 mr^2 + md^2
I*theta: = -mg(rsin(theta))

The Attempt at a Solution

1/2 ma^2 +md^2

Im missing something simple here...If someone could point me in the right direction it would be appreciated

Wait, can I use alpha= to T/I , then relate that to 2pi to find period?

 

[boardaddict]

Wait, can I use alpha= to T/I , then relate that to 2pi to find period?

If I did this right I get ;

pi((a^2)+d^2)/g*d

If someone would confirm that would be great