Force
Sir Isaac Newton described the motion of all objects using the concepts of inertia and force, and in doing so he found they obey certain conservation laws. In 1687, Newton published his thesis "Philosophiæ Naturalis Principia Mathematica". In this work Newton set out three laws of motion that to this day are the way forces are described in physics.
Experimental physics
Experimental physics is considered to have reached a high point with the publication of the "Philosophiae Naturalis Principia Mathematica" in 1687 by Sir Isaac Newton (1643–1727). In 1687, Newton published the "Principia", detailing two comprehensive and successful physical theories: Newton's laws of motion, from which arise classical mechanics; and Newton's law of universal gravitation, which describes the fundamental force of gravity. Both theories agreed well with experiment. The "Principia" also included several theories in fluid dynamics.