What are the Rotational Dynamics of a Thin Rod Held by a Pivot Point and String?

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superaznnerd
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rotational dynamics rod--please help!

Homework Statement


A thin rod of length l and mass m is fixed at a far ends by a free pivot and held from rotating with a string attached at 3/4l and fixed toa ceiling. The moment of inertia of a thin rod about a far end is ml2/3

a) what is the pivot point exerting on the rod

The rope is cut at t =0 seconds. at t =0 seconds find:
b) the angular acceleration of the rod.
c) the transverse acceleration of the rod's center of mass.
d) the transverse aceleration of point A (the far end of the rod)
e) the force exerted by the pivot point

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You have to at least try the problem and explain your thoughts before asking for help.
 


First, total downward torque = upward torque.
.5mgl + Torque of pivot point = .75mgl
torque of pivot point = .25mgl.
This doesn't make sense because the pivot point can't exert a torque.
Thats all I got to...and I couldn't figure out anthing else lol
I have all the answers, I just need to understand hwo to do it.