Angular acceleration

asi123

Hey guys.
I got this poll which is at one side connected to a wall and is being released from a horizontal state.
his length is L and mass m.
I need to find the angular acceleration of the poll as a function of the angle.
I got this answer in the pic but according to them the answer should be what I marked in the red box.

Any idea? am I wrong?

10x.

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asi123

Ok, I know what the problem is, I made a mistake in the moment of inertia...(Blush)

I do have another question due.(Nod)
First of all, when they say this is the angular acceleration of the poll, does it mean the angular acceleration of the center of mass?
In the next part of the question, they ask for the angular velocity as a function of $$\displaystyle \varphi$$.
I tried to use energy conservation and came up with this equation:
$$\displaystyle mgL=mgL(1-1/2\cos(\varphi))+1/2 mv^2+1/2 I\omega^2$$
When
$$\displaystyle v = \omega*(L/2)$$

Is this right?

10x.

asi123

Never mind guys, I got it.