Does Gravity Have Torque at the Pivot Point?

Thread starter auk411
Start date Nov 12, 2010
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Torque

AI Thread Summary

The discussion centers on whether gravity exerts torque at the pivot point, specifically when the pivot is at the roller. It is suggested that gravity does not produce torque at this point, but this is contingent upon the condition that h equals (L/2) sin(theta). The conversation emphasizes the importance of understanding the relationship between the pivot point and the gravitational force. Clarification of the torque concept in relation to different pivot positions is also highlighted. Ultimately, the resolution of the question hinges on the specific geometric relationships involved.

Nov 12, 2010

auk411

Homework Statement

here is an image: http://panda.unm.edu/Courses/Price/Phys160/F29-4.jpeg

Homework Equations

The Attempt at a Solution

My pivot point is at the roller. Doesn't that mean that gravity has no torque?

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Nov 12, 2010

ehild

Science Advisor

Homework Helper

auk411 said:

My pivot point is at the roller. Doesn't that mean that gravity has no torque?

It is only true if h=(L/2) sin(theta)

ehild

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