Reaction (physics)

As described by the third of Newton's laws of motion of classical mechanics, all forces occur in pairs such that if one object exerts a force on another object, then the second object exerts an equal and opposite reaction force on the first.^[1]^[2] The third law is also more generally stated as: "To every action there is always opposed an equal reaction: or the mutual actions of two bodies upon each other are always equal, and directed to contrary parts."^[3] The attribution of which of the two forces is the action and which is the reaction is arbitrary. Either of the two can be considered the action, while the other is its associated reaction.

^ Taylor, John R. (2005). Classical Mechanics. University Science Books. pp. 17–18. ISBN 9781891389221.
^ Shapiro, Ilya L.; de Berredo-Peixoto, Guilherme (2013). Lecture Notes on Newtonian Mechanics: Lessons from Modern Concepts. Springer Science & Business Media. p. 116. ISBN 978-1461478256. Retrieved 28 September 2016.
^ This translation of the third law and the commentary following it can be found in the "Principia" on page 20 of volume 1 of the 1729 translation.

[Taylor-1] Taylor, John R. (2005). Classical Mechanics. University Science Books. pp. 17–18. ISBN 9781891389221.

[2] Shapiro, Ilya L.; de Berredo-Peixoto, Guilherme (2013). Lecture Notes on Newtonian Mechanics: Lessons from Modern Concepts. Springer Science & Business Media. p. 116. ISBN 978-1461478256. Retrieved 28 September 2016.

[Scolium1-3] This translation of the third law and the commentary following it can be found in the "Principia" on page 20 of volume 1 of the 1729 translation.

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