Euler's laws of motion each governed by Newton’s laws of motion, then Euler’s equations can be derived from Newton’s laws. Euler’s equations can, however, be taken as axioms describing the laws of motion for extended bodies, independently of any particle distribution. The total body force applied to a continuous body with mass , mass density , and volume , is the volume integral integrated over the volume of the body: where is the force acting on the body per unit mass (dimensions of acceleration, misleadingly called the "body force"), and is an infinitesimal mass element of the body. Body forces and contact forces acting
Clarke's three laws Clarke's three laws British science fiction writer Arthur C. Clarke formulated three adages that are known as Clarke's three laws, of which the third law is the best known and most widely cited. They were part of his ideas in his extensive writings about the future. These so-called laws include: One account claimed that Clarke's "laws" were developed after the editor of his works in French started numbering the author's assertions. All three laws appear in Clarke's essay "Hazards of Prophecy: The Failure of Imagination", first published in "Profiles of the Future" (1962). However, they were not published at the