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## Homework Statement

Damped driven oscillator: ruler example. Suppose the ruler used in the classroom demonstration has a length of 12 and 13/16ths inches, a width of 1 ½ inches, is 1/16th inch thick with a density of 1.2 g/cm3. It swings from a pivot point ¼ of an inch from the top end.

a) Find the undamped frequency ω0 for this physical pendulum (ignore the hole except for locating the pivot point).

## Homework Equations

I don't know

## The Attempt at a Solution

I am sure I could find the frequency, I just don't know how to set up the problem. I drew a diagram and marked the forces acting on the pendulum.I am pretty sure since the ruler has uniform mass that the center of mass would be "bob" of the pendulum. but with the pivot point being located away from the edge, I am not sure how to affect the center of gravity.

What I want to say is that I should take the center of gravity to be the middle of the ruler below the pivot. Then I take the force of part of the ruler above the pivot and treat it like a lever. subtract the two forces and then treat the pendulum as if its pivot was on the edge, but it has the altered force at the center of the part of the ruler lieing below the pivot.

Is this the correct approach?

I went ahead with this approach. I found the torques on both sides of the pivot due to gravity. and then I subtracted the torque.

I plugged it into the equation for W{not} and got .776

is this correct?

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