A. De Ambrosis

Knowledge of air: A study of children aged between 6 and 8 years

The research presented here was carried out jointly by physicists and psychologists with the purpose of verifying whether participation in physical experiments together with social interaction (with adults and school‐mates) can favour childrens development of causal knowledge and their understanding of a physically complex problem. Children aged between 6 and 8 years were involved in a study of air and its properties. Tests show that exposing children of this age to a sequence of appropriate experiments which are carried out together with their class‐mates, leads them to give up pre‐causal explanations and to resort to physical ones.

Computer Simulation and Laboratory Work in the Teaching of Mechanics

By analysing the measures of student success in learning the fundamentals of physics in conjunction with the research reported in the literature one can conclude that it is difficult or undergraduates as well as high-school students to gain a reasonable understanding of elementary mechanics. Considerable effort has been devoted to identifying those factors which might prevent mechanics being successfully learnt and also to developing instructional methods which could improve its teaching (Champagne et al. 1984, Hewson 1985, McDermott 1983, Saltiel and Malgrange 1980, Whitaker 1983, White 1983). Starting from these research results and drawing from their own experience (Borghi et al. 1984, 1985), they arrived at the following conclusions. A strategy based on experimental activity, performed by the students themselves, together with a proper use of computer simulations, could well improve the learning of mechanics and enhance the interest in, and understanding of, topics which are difficult to treat in a traditional way. The authors describe the strategy they have designed to help high school students to learn mechanics and report how they have applied this strategy to their particular topic of projectile motion.

Teaching quantum physics by the sum over paths approach and GeoGebra simulations

We present a research-based teaching sequence in introductory quantum physics using the Feynman sum over paths approach. Our reconstruction avoids the historical pathway, and starts by reconsidering optics from the standpoint of the quantum nature of light, analysing both traditional and modern experiments. The core of our educational path lies in the treatment of conceptual and epistemological themes, peculiar of quantum theory, based on evidence from quantum optics, such as the single photon Mach–Zehnder and Zhou–Wang–Mandel experiments. The sequence is supported by a collection of interactive simulations, realized in the open source GeoGebra environment, which we used to assist students in learning the basics of the method, and help them explore the proposed experimental situations as modeled in the sum over paths perspective. We tested our approach in the context of a post-graduate training course for pre-service physics teachers; according to the data we collected, student teachers displayed a greatly improved understanding of conceptual issues, and acquired significant abilities in using the sum over path method for problem solving.

Microscopic models for bridging electrostatics and currents

A teaching sequence based on the use of microscopic models to link electrostatic phenomena with direct currents is presented. The sequence, devised for high school students, was designed after initial work carried out with student teachers attending a school of specialization for teaching physics at high school, at the University of Pavia. The results obtained with them are briefly presented, because they directed our steps for the development of the teaching sequence. For both the design of the experiments and their interpretation, we drew inspiration from the original works of Alessandro Volta; in addition, a structural model based on the particular role of electrons as elementary charges both in electrostatic phenomena and in currents was proposed. The teaching sequence starts from experiments on charging objects by rubbing and by induction, and engages students in constructing microscopic models to interpret their observations. By using these models and by closely examining the ideas of tension and capacitance, the students acknowledge that a charging (or discharging) process is due to the motion of electrons that, albeit for short time intervals, represent a current. Finally, they are made to see that the same happens in transients of direct current circuits.

Measuring the hydrogen Balmer series and Rydberg's constant with a homemade spectrophotometer

In a recent paper (Amrani 2014 Eur. J. Phys. 35 045001), the author presented two different methods to measure the wavelength of visible lines of Balmer series from the hydrogen atomic spectrum and estimate the value of Rydbergs constant with an error difference of a few tenths of a per cent. Here we discuss how low cost spectrometers, based on the use of either transmission or reflection diffraction gratings coupled with a commercial digital camera, can be employed with the same aim. The Rydbergs constant values obtained with our spectrometers are R = 1.096 ± 0.007 × 107 m−1 for the transmission grating spectrometer and R = 1.094 ± 0.005 × 107 m−1 for the reflection spectrometer, with a difference of less than 0.30% from the accepted value of 1.097 373 × 107 m−1.

The surprising rolling spool: experiments and theory from mechanics to phase transitions

An asymmetric rolling spool can be investigated as a simple model for a second-order phase transition. At low energy it undergoes librational motion around the equilibrium position, whereas at high energies its motion becomes rototranslational. The analysis of its dynamics shows that when approaching critical energy, the period of oscillation diverges; and this suggests the transition from one phase to the other. We thus show that the concept of ‘phase transition’, useful to describe the behaviour of a variety of thermodynamic systems, can be actualized in this simple mechanical system. Moreover, a tight analogy can be found between the rolling spool’s behaviour and the Tomlinson model of sliding friction. This analogy makes it possible to interpret the critical switch of static friction near the threshold of motion as a phase transition. The rolling spool can be easily constructed and used as a hands-on experiment. Quantitative measurements of its motion were carried out through open-source video analysis software.

Integrated computer simulations and the physics laboratory: a unit dealing with wave propagation

Abstract The work we present is part of a national project aimed at introducing the study of computer science in Italian schools and at favouring its use in the study of different curricular disciplines. Our research, dealing with the teaching of Physics, has resulted in a unit based on a close link between experiments and computer simulations. The topic we have chosen is wave propagation. We propose a simple model to illustrate how wave propagation originates and a computer based strategy to introduce the subject in high school.

Quantitative analysis of transmittance and photoluminescence using a low cost apparatus

We show how a low cost spectrometer, based on the use of inexpensive diffraction transmission gratings coupled with a commercial digital photo camera or a cellphone, can be assembled and employed to obtain quantitative spectra of different sources. In particular, we discuss its use in studying the spectra of fluorescent colored ink, used in highlighting pens, for which the transmission band and the emission peaks are measured and related to the ink color.

Teaching mechanical oscillations using an integrated curriculum

Abstract A set of teaching materials dealing with harmonic oscillations was developed as part of a research project investigating the influence of different pedagogical tools on physics learning. The materials incorporate simulation software and laboratory activities associated with Teacher and Student Units. The project involved research groups at seven Italian universities and the materials have been trialled in high schools nation‐wide. This paper describes the experimental protocol for the use of these materials in pilot classes and the evaluation of student learning and teacher training results. The intervention was found to improve physics education at school praxis level and to promote understanding of the content area as well as appreciation of the role of experiments and simulations in the construction of scientific knowledge

Logo programming and experiments to study motion in primary school

Abstract A research aimed at understanding childrens ideas on motion and at designing a teaching strategy to introduce the concept of average velocity in primary school is presented.