Force suspended on a vertical spring scale experiences the force of gravity acting on the object balanced by a force applied by the "spring reaction force", which equals the object's weight. Using such tools, some quantitative force laws were discovered: that the force of gravity is proportional to volume for objects of constant density (widely exploited for millennia to define standard weights); Archimedes' principle for buoyancy; Archimedes' analysis of the lever; Boyle's law for gas pressure; and Hooke's law for springs. These were all formulated and experimentally verified before Isaac Newton expounded his Three Laws of Motion. Dynamic equilibrium was first
Laws of technical systems evolution in TRIZ. The following authors, besides Altshuller, contributed most to it: Yuri Khotimlyansky (studied patterns of energy conductivity in technical systems), Vladimir Asinovsky (proposed principles of correspondence of various components of technical systems), Yevgeny Karasik (co-authored with Altshuller the law of transition from a macro-level to a micro-level, introduced the notion of dual technical systems and studied the patterns of their evolution). In his pioneering work of 1975, Altshuller subdivided all laws of technical systems evolution into 3 categories: Laws of technical systems evolution The laws of technical systems evolution are the most general evolution trends for technical systems discovered