Why do the forces not net out to zero in a system in static equilibrium?

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In a static equilibrium system, the sum of forces must equal zero, but the presence of a pivot point can create a scenario where forces do not appear to net out. For example, a wooden plank with a small mass on one end and a larger mass near the pivot can balance torques while still having unbalanced forces due to the pivot's upward support force. This upward force counteracts the downward forces from the masses, ensuring the system remains stationary. Understanding the role of the pivot is crucial in grasping why forces can seem unbalanced yet still maintain equilibrium. The clarification provided resolves confusion about the relationship between forces and torques in static systems.
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I understand that for a system to be in static equilibrium the sum of the forces and torques must equal zero. I understand why the torques must net out to zero but not the forces. For example, if you picture a wooden plank pivoted at the center with a small mass on the far left end and a very large mass near the pivot such that the torques net out to zero, the system is not moving yet the forces do not net out to zero. if somebody can please explain, I would be very appreciative.
 
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Don't forget that the pivot itself exerts an upward force to support the plank and the two masses.
 
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Doc Al said:
Don't forget that the pivot itself exerts an upward force to support the plank and the two masses.

oh my gosh! How could I forget that! Thank you very much.. its been bugging me for three days now.
 

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