Table of contents

The Swiss physicist Wolfgang Pauli (1900-58) descends from a notable Jewish family of publishers and booksellers in Prague. This essay presents biographical data and Prague fortunes of his father, grandfather and great grandfather. The roots of friendship between Wolfgang Pauli's father and the family of Ernst Mach, then a professor at the University of Prague, are documented and a hypothesis is suggested concerning the motives that induced Wolf Pascheles, Wolfgang Pauli's father, to choose the name 'Pauli' as his new surname.

Students' conceptions and difficulties about differentials have been investigated in mathematics and physics in an interdisciplinary investigation. The first results suggest that different conception of differentials coexist in students, linked with different contexts: an algebraic object in mathematics, a pure fiction or a 'little bit of something' in physics. Moreover, differentials and integral procedures are commonly used by students without any clear idea of what can require and legitimate them. Most often, the need as well as the validation rely in the students' minds on key words such as, for example, 'elementary'. These points and corresponding difficulties are discussed and some pedagogical suggestions are made.

The results obtained in two experimental studies performed during two academic years at the Science Faculty of Bari University (Southern Italy) are reported. In these two investigations the aims were: (i) to probe the students' understanding of the concept of velocity and to detect the reasoning adopted in solving the written problems proposed; (ii) to investigate the effect of the nature of the problems on the student samples (freshmen or sophomores) and the incidence of formal teaching of the concept of velocity at university level; (iii) to study the relationship between the intellectual level of cognitive development and the answer typologies identified. The authors were disappointed to find that as many as about 29% of the student sample exposed to careful lectures were still dominated by the so-called position-velocity misconception. Remedial activity based on the model of conceptual change was tried and proved to be successful in helping the students to acquire the concept of velocity correctly, and to remove their misconception.

A Monte Carlo simulation of a simple two-dimensional model of a water-like system is presented. A dilute solution of an apolar molecule in the same fluid is also described. The results of the two simulations will be compared in order to evidence the characteristics features of hydration around the solute particle. The objective of the described software is principally pedagogical in order to give students some insights concerning the structure of water and its role as a solvent.

The socio-technical, economic and cultural influences on the rise of American solid state physics and its relations to the national scientific 'styles' of Britain, France and Germany are considered. A key influence on the new science in America is found to be Slater and the Massachusetts Institute of Technology's close interactions with the American industrial electronics and photographic laboratories. Also important was the merging together in the inter-war period of the 'Anglo-American' (predominantly experimental) and the 'German' (predominantly theoretical) streams of physics, as well as the post-war merging of the civilian and military branches of American science. The article concludes with a discussion of the different national styles of solid state physics, and of the socio-cultural determinants of Slater's own most favoured approach.

In introductory relativity courses, the relativity of simultaneity is often introduced by showing that if two clocks on a uniformly moving relativistic plane are synchronised by the pilot, then they will not be synchronised in the fame of the ground. The author's beginning students have repeatedly asked: What happens if the pilot lands the plane? Mustn't the pilot and ground based observer, now in the same frame, agree? If so, on what do they agree? The article answers these questions consistently from two different points of view. Firstly, special relativity is used to calculate how the deceleration affects the plane's clocks during landing for a ground observer. Secondly, the principle of equivalence is used to calculate how the deceleration affects the clocks for an observer on the plane. Since both points of view use only elementary techniques, this calculation could be used to illustrate and reinforce concepts normally included in an introductory course.

A condition for thermodynamic equilibrium is derived, which is found to be a generalisation of the principle of virtual work, familiar in classical statics. The equilibrium condition makes no reference to thermodynamic potentials and is therefore applicable without the usual need to impose constraints other than those which are necessary to define the physical conditions of the problem.

The authors investigate the effect of finiteness of the heat reservoirs on the thermal efficiency of engines and performance coefficient of refrigerators, employing a Carnot cycle. The efficiency and the performance are both lowered in comparison to the case of machines working between reservoirs at constant temperatures.

The law of conservation of energy and the kinetic energy theorem have been used to establish the energetic balance sheet in the classical rocket example.