what objectives can we derive from adding forces, resultants and equilibriants?

Answer 1

By vector addition of forces we find the resultant of the forces.

If the resultant force is not zero we add a suitable force to make the resutant zero. The added new force is the equilibrant.

When a body is in equilibrium under the action of a number of forces, then each force is the equilibrant of the resultant of all other forces.

Answer 2

You can find the total vector force acting on a mass. And that usually tells you a fair amount about what that mass is doing.


Doug