Newton's first law of motion
If no external force acts on a particle, then it is possible to select a set of reference frames, called inertial reference frames, observed from which the particle moves without any change in velocity.
- Lex I: Corpus omne perseverare in statu suo quiescendi vel movendi uniformiter in directum, nisi quatenus a viribus impressis cogitur statum illum mutare. Principia Mathematica.
Newton's second law of motion
Where is the force, is the mass and is the acceleration. This law has been found to be true for accelerations as small as (Ref. 2)
- Lex II: Mutationem motus proportionalem esse vi motrici impressae, et fieri secundum lineam rectam qua vis illa imprimitur. Principia Mathematica.
- Frank Wilczek "Whence the Force of F = ma? I: Culture Shock", Physics Today October pp. 11-12 (2004)
- Frank Wilczek "Whence the Force of F = ma? II: Rationalizations", Physics Today December pp. 10-11 (2004)
- Frank Wilczek "Whence the Force of F = ma? III: Cultural Diversity", Physics Today July pp. 10-11 (2005)
- Adrian Cho "No Twisting Out of Newton's Law", ScienceNOW Daily News 13 April 2007
- J. H. Gundlach, S. Schlamminger, C. D. Spitzer, K.-Y. Choi, B. A. Woodahl, J. J. Coy, and E. Fischbach "Laboratory test of Newton's second law for small accelerations", Physical Review Letters 98 150801 (2007)
Newton's third law of motion
Whenever A exerts a force on B, B simultaneously exerts a force on A with the same magnitude in the opposite direction.
- Lex III: Actioni contrariam semper et æqualem esse reactionem: sive corporum duorum actiones in se mutuo semper esse æquales et in partes contrarias dirigi. Principia Mathematica.
- Interesting reading