Counterintuitive uniform bar torque question

AI Thread Summary
A uniform bar pivoted at its center of mass should theoretically remain in static equilibrium when rotated at an angle theta from the horizontal. However, in practice, achieving this balance is challenging due to the difficulty of precisely locating the pivot at the center of mass. As a result, the bar often swings until it reaches a horizontal position. The actual equilibrium orientation is influenced by the exact placement of the pivot point. This discrepancy highlights the difference between theoretical physics and real-world applications.
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The uniform bar in the attached diagram pivoted onto a wall on its center of mass and rotated an angle theta>0 from the horizontal should theoretically stay in static equilibrium because all torques are balanced, right?

How come trying to do this in real life usually leads to the bar swinging until the bar is horizontal?
 

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In real life, you rarely hit exactly the center of mass with a pivot. The real life equilibrium orientation will depend on where exactly the pivot is.
 
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