Line of action

The line of action or line of action is a term of Applied Mechanics and characterized together with the magnitude and direction a force vector. The action line is the straight line passing through the point of a force and the direction of the force has. All points on this line can be regarded as a point of strength. Thus, it is the straight line on which the point of application of force can be arbitrarily selected without changing the effect on a body. This is known as the principle of Linienflüchtigkeit, which applies to any force ( which is considered individually on its own).

In mathematics, are called vector only free vectors that can be moved to any room in parallel. In contrast, force vectors are (by their effect and torque, not to change ) bound to its line of action and line- volatile vectors are sometimes called.

The force couple action and reaction from the interaction principle lie on the same line of action. Your targets are, however, always in different bodies.