Engineering Mechanics: Notation question

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The discussion clarifies the calculation of moments in engineering mechanics, specifically regarding the notation used for the moment equation. The equation Moment = r (m/n) * F indicates that r (m/n) represents the vector from point N to point M. The direction of this vector must be perpendicular to the applied force, which, if applied along the y-axis, necessitates a moment direction along the x-axis. The moment is ultimately calculated using the vector cross product, expressed as M = rn/m x F, where the subscripts denote the application and reference points.

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In a problem involving moments where we have a 2 point is space: m and n.
We want the moment about M due to a force applied at N.
We know the equation is Moment = r (m/n) * F

So, does r (m/n) represent the (x,y,z) coordinates from the point N to M or M to N?
 
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The direction has to be perpendicular to the applied force. So, if the force is applied along the y axis, the direction should be in x axis. Hope that helps.
 
The calculation of a moment is usually done in vector (cross product) form,
M = required moment (a vector)
= rn/m x F

Note that, in the subscript on r, the first item is the point where F is applied while the second is the reference point for the moment.
 

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