Engineering Statics

C-3


Determine the magnitude of the couple generated by the forces shown.

Examining point A, we know that the moment is the result of a displacement vector from A to B crossed with the force vector at B.
The displacement vector from A to B is determined...
The force vector at point B is  determined...
The moment, then, is calculated.
For comparison, we examine the moment determined from 
point B, and see that the result is the same.
Similarly, calculating the sum of moments about an arbitrary point, say point D, results in the same solution.