A spring balance attempts to drag an object across a table, but the object does not move because of the force of friction acting on the body in an equal and opposite direction. When the forces acting upon an object are equal and opposite the object is said to be in a state of equilibrium. What are these forces called?
Equilibriant force is the force acting upon an object which are equal and opposite the object. Therefore it is equal in magnitude but opposite in direction to the resultant Force. hope I have helped you.