Understanding Torque: The Role of Axis of Rotation in Force Calculation"

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When calculating torque, forces acting directly at the axis of rotation do not contribute to the net torque because they create no perpendicular distance from the axis. Torque is defined as the product of force and the distance from the axis of rotation, and if the force acts at the axis, that distance is zero. This principle clarifies why such forces are disregarded in torque calculations. Understanding this concept is crucial for accurately analyzing rotational dynamics. Visual aids can enhance comprehension of these principles.
oneplusone
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Hello,

[1]-Why is it that if you have a force acting upon an object at the point of the axis of torque,
you don't account it in the equation when solving for torque?

Sorry, not really sure how to word it, but ill give it another shot:

You have a long piece of wood on the ground, with many forces acting upon it. On one side of
the wood, you choose the axis of rotation. One of the forces acts on this point at a 42 degree angle.

When calculating the net torque on the object, why do you disregard that force which acts on the point?

Thanks. and let me know if i should try to reword.
 
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Not making the connection. Perhaps a picture would help.
 
Torque is calculated about a chosen point on an axis. When the force acts through that point, there is no perpendicular distance from the force to the point.
 
Thanks, got it now!
 

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