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…

Of all the conceivable ideal-gas processes, almost all introductory physics textbooks as well as more advanced texts on thermodynamics emphasize only four: isochoric, isobaric, isothermal, and adiabatic (isentropic). These are processes in which a state variable--volume, pressure, temperature, or entropy--remains constant. It turns out that these…

We use the Survey of Thermodynamic Processes and First and Second Laws-Long (STPFaSL-Long), a research-based survey instrument with 78 items at the level of introductory physics, to investigate introductory and advanced students' difficulties with entropy and the second law of thermodynamics. We present an analysis of data from 12 different…

This paper starts with an introduction to the concept of momentum current. It is followed by a discussion of its strength and density with the aid of several analogies made between momentum current and electric current. Based on the novel concepts of thermal charge and its quantity (entropy), the analogies are extended to entropy current. The…

Using the analogy between thermodynamics and electricity, two new concepts of thermal charge and quantity of thermal charge are introduced. A simple yet explicit definition of entropy is then derived-entropy is the quantity of thermal charge. As a result, quantity of thermal charge (entropy) and quantity of heat (energy) are now clearly…

We discuss the development and validation of the long version of a conceptual multiple-choice survey instrument called the Survey of Thermodynamic Processes and First and Second Laws-Long suitable for introductory physics courses. This version of the survey instrument is a longer version of the original shorter version developed and validated…

Physics experts and students commonly use a variety of representations when working with partial derivatives, including symbols, graphs, and words. One especially powerful representation is the contour graph. In open-ended problem-solving interviews with nine upper-division physics students, we asked students to determine derivatives from contour…

Validated conceptual multiple-choice surveys administered before and after instruction in relevant concepts can be useful tools to gauge the effectiveness of curricula and pedagogical strategies. Here we discuss the use of four different validated surveys to investigate student understanding: The Energy and Momentum Conceptual Survey (EMCS), the…

Why do we need to pour less water in an egg steamer to prepare more eggs to the same degree of 'doneness'? We discuss the physical processes at work in the electric egg steamer and resolve this seeming paradox. We demonstrate that the main heat transfer mechanism from steam to egg is due to latent heat through condensation. This not only explains…

Thermodynamics education is not easy both for students and teachers. But the Entropy, Chemical potential, Real gas structure, Fugacity, Molecular interaction, Supercritical phenomena chapters become more comprehensible, if introduced via the pure real gases' cluster physics chapter. A pure gas consists of the only one type of basic particles,…

We use the Survey of Thermodynamic Processes and First and Second Laws-Long, a research-based survey instrument with 78 items at the level of introductory physics, to investigate introductory and advanced students' difficulties with internal energy, work, and heat transfer. We present analysis of data from 12 different introductory and advanced…

Thermodynamic processes are often presented in so called P-V diagrams and the processes are often isobaric, isochoric, isothermal, and adiabatic. The purpose of the qualitative research reported here was to explore students' reasoning and interpretation of P-V diagrams that were presented by the help of GeoGebra. The research group had 15 students…

Statistical mechanics has received limited attention in physics education research and remains a relatively underrepresented topic even in research on upper-division physics courses. The purpose of this study was to explore potential challenges that physics students encounter when they solve statistical mechanics problems in groups. Adopting a…

In early January 2018, after days of subfreezing temperatures, a 20 m waterfall became mostly frozen with supercooled water pouring over the top of the frozen parts of the fall. A video was taken of the waterfalls and supercooled turbulent water flowing on the frozen surface as it turned into frazil ice right before our eyes. Frazil ice consists…

Keto-enol tautomerism is a fundamental concept that examines the migration of a proton between two constitutional isomers, the keto and enol tautomer. Many experiments have been proposed to understand the concept behind Meyer's Rule, which states that the keto tautomer is favored as the solvent polarity increases. However, all the experiments have…