An experiment analogous to that devised by Grimaldi and subsequently repeated by Young to study the nature of light has been realized with electrons. Following the Grimaldi and Young line of thought, an original approach is presented to introduce undergraduate physics students to the wave behaviour of electrons. An electron microscope equipped…

The solution to the Euler-Lagrange equation is an extremal functional. To understand that the functional is stationary at local extrema (maxima or minima), we propose a physics experiment that involves using a soap film to form a catenoid. A catenoid is a surface that is formed between two coaxial circular rings and is classified mathematically as…

A recent article by Morse described interesting electrostatics experiments using an MBL charge sensor. In this application, the charge sensor has a large capacitance compared to the charged test object, so nearly all charges can be transferred to the sensor capacitor from the capacitor to be measured. However, the typical capacitance of commercial…

The effect of density inversion on the convective flow of water in a spherical glass flask cooled with the help of an ice-water bath is shown. The experiment was carried out by temperature measurements (cooling curves) taken at three different heights along the vertical diameter of the flask. Flows inside the flask are visualized by seeding the…

The quantization of electronic energy levels in atoms is foundational to a mechanistic explanation of the periodicity of elemental properties and behavior. This paper presents a hands-on, guided inquiry approach to teaching this concept as part of a broader treatment of quantum mechanics, and as a foundation for an understanding of chemical…

In delivering chemistry courses by distance, a key challenge is to offer the learner an authentic and meaningful laboratory experience that still provides the rigour required to continue on in science. To satisfy this need, two distance general chemistry laboratory courses appropriate for Bachelor of Science (B.Sc.) students, including chemistry…

The main aim of this study was to examine how a group of elementary students perceived their engagement in a project-based science intervention investigating the water quality of a local lake. The students collaborated with a scientist to conduct various experiments and used handheld computers to collect and analyze data in order to examine the…

The objective of this study was to develop an online report writing activity that was a constructive and cooperative learning process for a course on traditional general physics experiments. Wiki, a CMC authoring tool, was used to construct the writing platform. Fifty-eight undergraduate students (33 men and 25 women), working in randomly assigned…

Mating between closely related individuals often causes reduced fitness, which is termed "inbreeding depression". Inbreeding is, therefore, a threat towards the persistence of animal and plant populations. Here we present methods and results from a practical for high-school and first-year university students and discuss learning outcomes…

This short article describes some useful and quick applications of a cooking electronic balance. Newton's third law, Archimedes buoyancy and an estimate of relative density are accomplished in a very simple way. (Contains 1 figure.)

This article presents a lab experience to study detergency from a physicochemical point of view intended for undergraduate students. By means of a simple experimental device, we analyze the influence of the surfactant concentration in both distilled water and tap water. Our method is based on the measurement of diffuse reflectances of polyester…

A simple in class laboratory illustrating the principles of ion exchange chromatography as a bioseparation technique is described. A protein's isoelectric point as a driving force for ion exchange chromatography is easily demonstrated by using combinations of proteins with natural color or fluorescence, such as DsRed2, enhanced green fluorescent…

The predator-prey relationship is one of the most recognizable and well-studied animal relationships. One of the more striking aspects of this relationship is the differential natural selection pressure placed on predators and their prey. This differential pressure results from differing costs of failure, the so-called life-dinner principle. If a…

Purpose: Owing to the specialist nature of biological experimentation, scientific research staff have been largely neglected from the pro-environmental initiatives which have inundated other areas of higher education. This dearth of studies is surprising given that scientific research is recognised as a substantial contributor to the environmental…

Scientific freedom and openness are hallmarks of academia: relative to their counterparts in industry, academics maintain discretion over their research agenda and allow others to build on their discoveries. This paper examines the relationship between openness and freedom, building on recent models emphasizing that, from an economic perspective,…