# Newtons laws

## Contents

## Newton's first law of motion[edit]

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.

#### In Latin[edit]

*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[edit]

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)

#### In Latin[edit]

*Lex II: Mutationem motus proportionalem esse vi motrici impressae, et fieri secundum lineam rectam qua vis illa imprimitur.*Principia Mathematica.

#### Interesting reading[edit]

- 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)

#### References[edit]

- 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[edit]

Whenever A exerts a force on B, B simultaneously exerts a force on A with the same magnitude in the opposite direction.

#### In Latin[edit]

*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