Newton's laws of motion to forces is a straight line at a constant speed. Newton's first law is often referred to as the "law of inertia". Thus, a condition necessary for the uniform motion of a particle relative to an inertial reference frame is that the total net force acting on it is zero. In this sense, the first law can be restated as: Newton's first and second laws are valid only in an inertial reference frame. Any reference frame that is in uniform motion with respect to an inertial frame is also an inertial frame, i.e. Galilean invariance or the principle of Newtonian
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