# If force is a localized vector, what does it's resultant mean?

And how is the resultant formally calculated? Why do we treat force as a free vector when writing down Newton's Laws of motion?

As for the resultant, when you are concerned with rotations of an object, you calculate resultant treating forces like free vectors, but you have to localize resultant at the point, where lines of forces intersect (refer the figure, where $R$ is a resultant of $F_1$ and $F_2$). Your object will not rotate if and only if line of resultant force goes through the object's center of inertia.