The inverted torsional pendulum (often used as a tool to study non-linear oscillations and the transition to deterministic chaos) is here compared to an electric non-linear oscillator which shows a quite similar dynamic behaviour: the motion equation of the second system is exactly described by the Duffing equation, […]
This article describes a simple method to experiment the relation Q/V=const, by means of the direct measurement of Q and V. The necessary equipment can be easily found in any physics laboratory, as it is basically made of a 0-600V dc generator, […]
In this work it is shown how it is possible to build a simple device: the dripping faucet. This physical system exhibits an extremely interesting dynamic behaviour, useful to introduce the subject of deterministic chaos in high schools […]
Triboluminescence was studied using a self-built 8-litre vacuum chamber operated at a pressure of about 1mtorr. Luminescence is observed in the chamber along the peeling line of an unrolled adhesive tape. The tribo-mechanism produced electrons and X-rays are revealed by the intense luminescence of a BGO crystal positioned close to the peeling line. […]
A simple dissipative mechanical system is discussed in order to introduce, at high school level, the basic ideas on which are founded some typical experimental techniques concerning condensed matter. Some reflections are made concerning the passage from a macroscopic description to a microscopic one. […]
The Lenz law is studied experimentally using a permanent magnet falling inside metal tube. A home made force sensor is used to measure the weight of the tube and steady magnet before the experiment, and then to weight the vertically suspended tube when the magnet is dropped. […]
An ingenious and amusing activity originally devised by Dirac illustrates a topological symmetry property of the three-dimensional rotation of solids. Some mathematical aspects of this property and its relevance to the quantum physics description of fermions are explained. […]
This article shows how students can be taught the concept of using a transducer to measure the temperature with a very simple electronic circuit in which a NTC thermistor acts as sensor. Only a basic knowledge of the main properties of transistors and thermistors is required. […]
This paper presents the results of an enquiry on the ideas about Structure of Matter initially held by secondary school students. […]