# Newton's laws of motion

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## Newton's laws of motion

three laws that relate the forces and motions of bodies or objects (from the viewpoint of a fixed observer), first proposed by Isaac Newton. (1) An object will remain at rest or continue with constant velocity unless acted on by an unbalanced force. (2) The rate of change of momentum (or acceleration for a body/object of constant mass) is proportional to, and in the same direction as, the force applied to it (force = mass ×1 acceleration). (3) When two objects are in contact, the force applied by one object on the other is equal and opposite to that of the second object on the first (for every action, there is an equal and opposite reaction).## law

principle or rule*Davis' law**Hilton's law**Hook's law**inverse-square law*^{2})*law of excitation**Newton's first law; law of inertia**Newton's second law; law of acceleration**Newton's third law; law of reciprocal actions**Pascal's law**Poiseuille's law**Starling's law**Wolff's law**see*bone modelling)