# Newton’s Use of the Pendulum to Investigate Fluid Resistance: A Case Study and some Implications for Teaching About the Nature of Science

- 117 Downloads
- 3 Citations

## Abstract

Books I and III of Newton’s *Principia* develop Newton’s dynamical theory and show how it explains a number of celestial phenomena. Book II has received little attention from historians or educators because it does not play a major role in Newton’s argument. However, it is in Book II that we see most clearly Newton both as a theoretician and an experimenter. In this part of the *Principia* Newton dealt with terrestrial rather than with celestial phenomena and described a number of experiments he carried out to establish the success of his theory in explaining the properties of fluid resistance. It demonstrates most clearly the activities of a scientist working at the forefront of knowledge and working with phenomena which he did not fully understand. In this paper the first of Newton’s set of experiments into fluid resistance are described and the theory which underlies his explanation is outlined. A number of issues arising from this portion of the *Principia* together with implications for teaching about the nature of science are discussed.

## Keywords

Irrelevant Variable Fluid Resistance Pendulum Length Pendulum Parameter Celestial Phenomenon## References

- Aiton EJ (1972) The Vortex Theory of Planetary Motion. Science History Publications, New YorkGoogle Scholar
- Chandrasekhar S (1995) Newton’s Principia for the Common Reader. Oxford University Press, OxfordGoogle Scholar
- Cohen IB (1971) Introduction to Newton’s Principia. Cambridge University Press, CambridgeGoogle Scholar
- Densmore D (1995) Newton’s Principia: The Central Argument. Green Lion Press, Santa Fe, NMGoogle Scholar
- Gauld CF (1998) Colliding Pendulums, Conservation of Momentum and Newton’s Third Law. Australian Science Teachers Journal 44(3):37–38Google Scholar
- Gauld CF (1999) Using Colliding Pendulums to Teach Newton’s Third Law. The Physics Teacher 37:25–28CrossRefGoogle Scholar
- Gauld CF (2004) The Treatment of Cycloidal Pendulum Motion in Newton’s
*Principia*. Sci Educ 13:663–673CrossRefGoogle Scholar - Kidd RB, Fogg SL (2002) A Simple Formula for the Large-angle Pendulum Period. The Physics Teacher 40:81–83CrossRefGoogle Scholar
- Koyré A (1965) Newtonian Studies. Chapman & Hall, LondonGoogle Scholar
- Newton I (1729/1960) The Mathematical Principles of Natural Philosophy, (translated from the third edition by Andrew Motte and revised by Florian Cajori). University of California Press, Berkeley, CAGoogle Scholar
- Truesdell C (1968a) A Program toward Rediscovering the Rational Mechanics of the Age of Reason. In: Truesdell C (ed) Essays in the History of Mechanics. Springer-Verlag, Berlin, pp 85–137Google Scholar
- Truesdell C (1968b) Reactions of late Baroque Mechanics to Success, Conjecture, Error, and Failure in Newton’s
*Principia*. In: Truesdell C (ed) Essays in the History of Mechanics. Springer-Verlag, Berlin, pp 138–183Google Scholar - Westfall RS (1973) Newton and the Fudge Factor. Science 179:751–758CrossRefGoogle Scholar
- Westfall RS (1980) Never at Rest: A Biography of Isaac Newton. Cambridge University Press, CambridgeGoogle Scholar
- Westfall RS (1990) Making a World of Precision: Newton and the Construction of Quantitative Physics. In: Durham F, Pennington RD (eds) Some Truer Methods: Reflections on the Heritage of Newton. Columbia University Press, New York, pp 59–87Google Scholar