Another simple torque question

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To calculate the resulting angular and linear acceleration of a rod rotating around a pivot, use the equation τ = Ipivotα for angular acceleration. Linear acceleration must be specified for a particular point on the rod, as all points describe circular motion around the pivot. Understanding the forces that cause rotation around the pivot, rather than the center of mass, requires determining the horizontal and vertical components of the pivot's force on the rod. This approach clarifies how the addition of a pivot alters the dynamics of the system. The discussion emphasizes the importance of distinguishing between rotational and translational motion in rigid bodies.
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In this diagram:

[PLAIN]http://img827.imageshack.us/img827/2853/physicsqb.png

how do I calculate the resulting angular and linear acceleration?

if I want to consider the result as a combination of a rotation and a translation?

or, in other words, I don't want to say "there is a pivot" I want to say "what are the forces that result in the rod rotating around the pivot as opposed to its center of mass" ?

or "how can I explain the change in outcome due to adding that pivot" ?
 
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WildEnergy said:
In this diagram:
how do I calculate the resulting angular and linear acceleration?
You use τ = Ipivotα to calculate the angular acceleration. It makes no sense to ask about the linear acceleration unless you specify the point whose linear acceleration you are interested in.

if I want to consider the result as a combination of a rotation and a translation?
Exactly what is it that undergoes a combination of rotation and translation in this case? All the points on this rigid body describe circles of various radii centered at the pivot.

or, in other words, I don't want to say "there is a pivot" I want to say "what are the forces that result in the rod rotating around the pivot as opposed to its center of mass" ?
or "how can I explain the change in outcome due to adding that pivot" ?
Then you need to find expressions for the horizontal and vertical components of the force exerted by the pivot on the object.
 
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