Popular Explanations of Physical Phenomena: Broken Ruler, Oxygen in the Air and Water Attracted by Electric Charges

Hector G. Riveros

Hector G. Riveros Universidad Nacional Autónoma de México

Abstract

The inquiry-based approach to learning has proven to be quite effective, since Socrates, but it is difficult to found good questions to induce reasoning. Many sources explain wrongly some experimental results, which can be used as discrepant events. Some use the breaking of a ruler with a newspaper to "show" that the atmospheric pressure is powerful or "measure" the oxygen in the air using a burning candle or "explain" that electric charge
attracts the water because the dipolar properties of the water molecule. Those are seemingly reasonable explanations but they are not true. Those demonstrations can be used to promote discussion and understanding from very simple reasoning.

References

Amery, H. (1978). Como hacer Experimentos. Madrid: Pinto
Chiaverina C (2012). http://www.thescienceoutlet.com/EmailContent/Newsletter_2.aspx
de Vries L (1974) The book of Experiments. London: Murray
Helmentine, A. M. (2012). http://chemistry.about.com/od/chemistryexperiments/ht/bendwater.htm
Herbert, D. (1965). Mr. Wizard’s Science Secrets. New York: Hawthorn
Hewitt, P. (1994). Figuring Physics. Phys. Teacher 32, 254
Knill, O. (2006). http://www.math.harvard.edu/~knill/pedagogy/waterexperiment/index.html
Leeming J (1954) The Real Book of Science Experiments. New York: Garden City
Mandell M (1968) Physics Experiment for Children. New York: Dover
Montoya M (2012) http://www.youtube.com/watch?v=_3akakKYqhM&feature=related
Perelman Y (1975) Problemas y Experimentos Recreativos. Moscu:Mir
Pople S (1997) Física Razonada. Mexico City: Trillas
Questacon (2012 http://sciencesquad.questacon.edu.au/activities/ruler_break.html
Rahi GS (2012) http://faculty.uncfsu.edu/grahi/atmospheric.htm
Riveros, H.G., Ovalle, P., Lara, J.A. (2000). Oxygen Measurement in Gas Mixtures, Revista Sociedad Química de México 44, 101-103
Riveros, H.G. (2010). http://www.fisica.unam .mx/personales/hgriveros
Vivian, C. (1967). Science Experiments & Amusements for Children. New York: Dover
Sadler, W. (2012). http://www.sciencemadesimple.co.uk/page30g.html
SciencesFunFunFun. (2008). http://www.youtube.com/watch?v=ywJBZlS81c4
SkySkull. (2008). http://skullsinthestars.com/2011/05/27/water-has-properties-that-arepositively-electrifying/
Spangler, S. (2012). http://www.stevespanglerscience.com/experiment/heavy-newspaper-airpressure-science
Wikipedia. (2012). http://en.wikibooks.org/wiki/School_Science/ Atmospheric_pressure_demonstration.htm