Newton's laws of motion

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Related to Newton's first law: Newton's law of gravitation, Law of inertia

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).


principle or rule
  • Davis' law soft tissues' tendency to shorten and contract unless subject to frequent stretching

  • Hilton's law a joint and its motive muscles (+ insertions) are all supplied by the same nerve

  • Hook's law tissue strain (i.e. change in length) is directly proportional to applied compressive or stretching stress, so long as tissue elasticity (recoil ability) is not exceeded

  • inverse-square law radiation intensity is inversely proportional to square of distance from radiation source (rad = κ1/cm2)

  • law of excitation muscle tissue contracts in direct proportion to stimulating current strength

  • Newton's first law; law of inertia an object at rest will not move until acted upon by a force; an object in motion will remain in motion at constant velocity until acted on by a net force

  • Newton's second law; law of acceleration acceleration is directly proportional to applied force and indirectly proportional to object mass (i.e. force = mass × acceleration)

  • Newton's third law; law of reciprocal actions to every action there is an equal and opposite reaction; i.e. a body is maintained at rest by equal and opposing forces

  • Pascal's law a fluid at rest transmits pressure equally in every direction

  • Poiseuille's law vascular blood flow is inversely proportional to fourth power of vessel radius (i.e. the narrower the vessel, the greater the resistance to flow)

  • Starling's law the greater the stretch imposed on a circular muscle (e.g. muscle layer of an artery), the greater its reciprocal recoil and contraction

  • Wolff's law bone function changes cause bone structure modification (see bone modelling)

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In order to show that inertia and Newton's First Law are natural in the Aristotelian sense, I now want to consider Aristotle's conception of nature.
Newton's First Law could be the consequence of a more general principle, of which the principle of inertia is only a particular case.
Discuss what modifications they made, how the marble moved after it was ejected, and how they saw Newton's First Law in action.
Law Definition Example Newton's First Law Newton's Second Law Newton's Third Law
Newton's first law of motion states that all objects have inertia, or resistance to change in motion.
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According to Newton's first law of motion, when Newman's car slammed into the wall, his body continued flying at a constant velocity until a force--such as his seat belt--acted on it.
Meanwhile, thanks to Newton's first law of motion (see Nuts & Bolts, below), his body tried to continue on a straight path.
Newton's first law of motion describes it this way: An object moving at a steady velocity (speed and direction) keeps moving at that velocity unless acted on by an outside force.
The answer begins with Newton's first law of motion, or the law of inertia, which states that moving objects keep moving in a straight line unless acted on by an outside force.
Helping her maneuver is Newton's First Law of Motion
According to Newton's first law of motion, an object at rest remains at rest unless acted upon by an outside force.