# １６　Newtonian mechanics【What is the Universe？】Dialogue with the Universe

１６　Newtonian mechanics【What is the Universe？】Dialogue with the Universe
・Three laws of Newtonian mechanics
1) Law of inertia・・・As for an object, unless power acts -- stillness -- linear uniform motion is carried out.
2) Equation of motion・・・At a mass point the acceleration(a) is proportional to the power(F) of acting then, and is in inverse proportion to the mass(m).
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3) Action-reaction law
・Law of universal gravitation

※Newtonian mechanics can be used when treating movement of sufficiently later than the velocity of light in a macroscopic scale. For example, in the space navigation in an artificial satellite or planetary exploration, it is calculable in sufficient accuracy using Newtonian mechanics in many cases.