Bar holding a weight (conceptual)

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In the scenario of a rotating bar with a weight at its end, gravity acts downward on the weight, creating a potential for the bar to turn. However, the bar remains stable and does not rotate, indicating that a counteracting force is present. This force is centripetal force, which keeps the weight from moving closer to the axis of rotation. The discussion highlights the balance of forces required to maintain the system's equilibrium. Understanding these forces is crucial for analyzing rotational dynamics.
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A long, thin metal (massless) bar is rotating in a circle at constant velocity, perpendicular to the axis of rotation. A weight is placed on the end of the bar such that there is no vertical movement of the weight or bar. What force counteracts the force of gravity on the weight?.
 
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SkittleJuice said:
Are you sure http://en.wikipedia.org/wiki/Centripetal_force" is the right force?

Gravity is attempting to pull the weight down, which would turn the bar.

If the bar turned, the weight would get closer to the axis of rotation.

Is there a force that might be against the weight getting any closer to the axis of rotation?

;)

(My post in your homework problem question thread. It really was just me posting both places because this question is about the same problem that you were having trouble with that you posted about in the homework forum.)
 
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