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.
Law Definition Example Newton's First Law An object at rest Keeping a hockey sled tends to stay at rest.
Newton's first law of motion states that all objects have inertia, or resistance to change in motion As an object's mass increases, so does its inertia An increased yo-yo mass makes it harder to stop the toy once it starts spinning.
Explain the action in terms of Newton's first law of motion.
With no outside force acting on the skis, Newton's first law of motion turned from friend to foe: Picabo's body continued to fly in the direction of her velocity--straight into a fence.
The second part of Newton's first law of motion states that objects in motion stay in motion until acted on by an outside force.
Remember Newton's First Law of Motion: Once something is in motion, it will keep going until some external force stops or changes it.
This is where Newton's first law of motion comes into play.
Helping her maneuver is Newton's First Law of Motion (also called the law of inertia): An object at rest tends to remain at rest, and an object in motion tends to continue moving at a constant speed and in a straight line unless acted on by an outside force.
According to Newton's first law of motion (also called the law of inertia), he would continue moving horizontally until a force made him stop or change direction.