Question

a couple moment is a free vector or bound vector or both​

Answer 1

HEY -:)

A couple moment is a free vector.

Answer 2

Let us consider two forces that are equal in magnitude and opposite in direction. Let these two forces be at a distance d  from each other. As the question asks why couple moment is a free vector. I assume you know what the couple moment in this case will be.

In the above derivation ’A’ is an arbitrary point. Therefore this will be true for all points. This means the couple moment is same at all points, therefore it is a free vector.