Is the Proof Behind Choosing Any Point on an Axis to Calculate Torque?

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To calculate torque about an axis, any point on that axis can be chosen, and the torque can be determined by considering its components. The torque is split into two components: one parallel to the axis and another orthogonal to it. The orthogonal component attempts to change the axis's orientation, which is countered by an equal and opposite reactive torque from supporting structures. This balance leaves only the component parallel to the axis as the effective torque. Thus, the theorem is supported by the interaction of these torque components and their effects on the axis.
Ajaysabarish97
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I know that to calculate the torque about an axis, we can choose any point on that axis and find the torque about that point and take the component along the direction of the axis.Buy what is the proof behind this theorem?
 
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Split the torque into two components, one parallel to the axis and the other orthogonal to it. Then the second one is trying to change the orientation of the axis and so will be resisted by an equal and opposite torque applied by whatever structures hold the axis in place, such as bearings and wheel struts. When we add in that reactive torque, we are left with the component parallel to the axis.
 

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