noun
point of action; point of application
Physics term for the point where a force is applied, e.g. on a lever. Used in mechanics and engineering contexts.
てこの作用点に力を加える。
Apply force to the point of action of the lever.
作用点の位置を変えると、必要な力が変わる。
Changing the position of the point of application changes the required force.
力点 is the point where effort is applied, often synonymous with 作用点, but 作用点 is more general for any applied force.
Compound of 作用 (action, effect) and 点 (point). A straightforward technical term.