In this research, an educational approach to the concept of energy is proposed. It is based on the history of physics. In 1854 Hermann Hemlholtz gave a popular lecture on the recent discovery that energy is conserved. Such lecture is used as a guide to introduce the pupils within several nuances of this concept. Not much mathematics is used, so…

Geologists have always embraced the time arrow in order to reconstruct the past geology of Earth, thus turning geology into a historical science. The covert assumption regarding the direction of time from past to present appears in Nicolas Steno's principles of stratigraphy. The intuitive-metaphysical nature of Steno's assumption was based on a…

This paper is the first part of a three-part project "How the principle of energy conservation evolved between 1842 and 1870: the view of a participant". This paper aims at showing how the new ideas of Mayer and Joule were received, what constituted the new theory in the period under study, and how it was supported experimentally. A…

Fluorescence and phosphorescence are two forms of photoluminescence used in modern research and in practical applications. The early observations of these phenomena, before the emergence of quantum theory, highlight the investigation into the mechanism of light emission. In contrast to incandescence, photoluminescence does not require high…

The historical development of the classical postulates of the second law of Thermodynamics can be traced back to the book by Sadi Carnot, "Reflections on the motive power of fire." While unique in its own right and in some sense revolutionary, the book starts with an analogy between heat engines and waterwheels. Waterwheels were common engines of…

With this paper, our main aim is to contribute to the realisation of the chemical reactivity concept, tracing the historical evolution of the concept of chemical affinity that eventually supported the concept of chemical equilibrium. We will concentrate on searching for the theoretical grounds of three key chemical equilibrium ideas: "incomplete…

At first almost ignored and unread, Sadi Carnot's analysis of heat engines--published 150 years ago--contained ideas and methods that were developed later by Clausius and Thomson. Carnot's ideas and their influence on later science are discussed. (Author/RH)

Presents the history surrounding the evolution of the second law of thermodynamics. Discusses Sadi Carnot's contributions, but also refers to those by Clapeyron, Thomson, Joule, Clausius, and Boltzman among others. (RR)

Traces electronegativity in four fundamental areas of chemistry during the period 1870-1910: (1) the relationship between electronegativity and classical valence; (2) the relationship between electronegativity and periodic law; (3) the relationship between electronegativity thermochemistry; and (4) the relationship between electronegativity and…

The classical vacuum of physics is not empty, but contains a distinctive pattern of electromagnetic fields. Discovery of the vacuum, thermal spectrum, classical electron theory, zero-point spectrum, and effects of acceleration are discussed. Connection between thermal radiation and the classical vacuum reveals unexpected unity in the laws of…

Briefly mentions pre-19th century ideas and discusses the contributions of Mohr, Seguin, Mayer, Grove, Colding, Joule and Helmholtz and the controversies regarding priority including Tyndall's involvement in one of them. Mentions the tension between philosophical and practical modes of thought in 19th century science. Includes portraits. (GH)

Presents a chronicle of the life of American born Benjamin Thompson. His private life as well as descriptions of his scientific experiments are discussed. (CP)

This historical survey describes the contributions made to the field of physics by the National Bureau of Standards since its inception in 1901. Four broad areas are emphasized: nuclear physics, thermal physics (including cryogenics), spectroscopy and fundamental constants. (BT)

Analyzes students' misunderstanding of basic thermodynamic concepts on historical grounds. Finds that the persistence of some ideas from the caloric model are reinforced by magnitude names and unit definitions that were brought up at the early stages of thermodynamic development. Explores the failure of many popular textbooks to make a clear…