Statics
briefly, the dynamics of equilibrium, as kinetics is the dynamics of motion. In modern phraseology they are said to make up together the science of dynamics, since both deal with the effects of forces. According to Newton's first and second laws of motion, change of motion in a given mass indicates the existence of a force which is E descending, the problem is one of kinetics; but when it reaches the surface of the the earth its motion relatively relatively to the earth ceases, there is no acceleration, and the problem becomes statical. Every kinetical problem may be reduced to a statical problem by introducing into the material system forces whose effects will balance the various accelerations to which the different parts of the system are subject.