Implementing smartphones with their internal sensors into physics experiments represents a modern, attractive, and authentic approach to improve students' conceptual understanding of physics. In such experiments, smartphones often serve as objects with physical properties and as digital measurement devices to record, display, and analyze…

A simple measurement of the refractive index of a liquid has been performed using a spherical lens. This lens is a spherical shape flask containing the liquid under study. Parallel pointer laser beams are directed to the lens to obtain the back focal length of the lens. The focal point is determined visually or using the Tracker software to…

Astrophotography has been responsible for the discovery of planets, solar systems, stars, and several other celestial objects, which directly helps with expanding our knowledge about the universe and creating scientific models for nature. Practical techniques have been extensively described, including Covington, who has published an extensive…

Substantial research in teaching and learning has supported the use of active learning strategies in the classroom to improve student learning of fundamental physics concepts and problem-solving skills. The use of worksheets in class has become a widespread successful practice. In this paper, we analyzed numerous completed student worksheets to…

Science and engineering students in the second semester of a calculus-based physics sequence typically study and measure the on-axis magnetic field for a multiple, circular turn coil. There are four benefits to this approach: 1) an analytical solution is easily obtained, 2) the coil is easily constructed using tightly wound, high-gauge wire where…

The question from the title is raised because in almost all introductory physics courses/textbooks the atmospheric pressure has been attributed to the weight of the column of air from a given level in the atmosphere up to its top. "Air is pressing on air." However the same textbooks, in the chapter on the kinetic theory of gases, tell…

The floating and sinking phenomenon related to buoyant force can readily be observed in everyday life and easily demonstrated to young students. However, many students believe that the buoyant force is determined by the object's attributes, such as the shape (e.g., ship) or material (e.g., wood). As a result, students find it challenging to…

Owing to the presence of the Coriolis effect, the rotation of Earth has a multitude of surprising consequences that make the mechanics of the atmosphere or the oceans different from that of a fluid in a container. Since the Coriolis effect also captures the imagination of screenwriters, contributing to the continual exposure of students to bogus…

Look along the shelves holding your laboratory apparatus and into the demo-prep room, and you will find apparatus by "Cenco" and "The Central Scientific Company" sharing space with your new PASCO equipment. At the 1989 AAPT meeting in San Luis Obispo I was asked to talk about Cenco in honor of one of its long-term employers and…

The mechanical transmission of motion, which is observable in gears' turning direction (TD) and turning speed (TS) can be understood as part of the core concept "force and motion". Previous studies have suggested that most children before the age of nine have naïve concepts of gears' TD and TS. However, these studies relied on children's…

We investigated whether continuously alternating between topics during practice, or interleaved practice, improves memory and the ability to solve problems in undergraduate physics. Over 8 weeks, students in two lecture sections of a university-level introductory physics course completed thrice-weekly homework assignments, each containing problems…

While graduate admissions in physics directly affects only a small number of people on an annual basis, the number of people indirectly affected is orders of magnitude greater. Those who complete graduate degrees in physics will go on to become leaders in industry, government, and academia, with the latter educating the next generation of leaders…

Many teachers like to introduce the Bohr atom toward the end of an introductory physics course. This is an excellent idea, given the historic importance of Bohr's 1913 work, which provided the bridge from Planck's quantized interaction of matter and radiation (1900) to the full theory of quantum mechanics (1925-28). Unfortunately, the version of…

A little-known type of nuclear reactor called the "molten salt reactor" (MSR), in which nuclear fuel is dissolved in a liquid carrier salt, was proposed in the 1940s and developed at the Oak Ridge National Laboratory in the 1960s. Recently, the MSR has generated renewed interest as a remedy for the drawbacks associated with conventional…

Thundercloud charge separation, or the process by which the bottom portion of a cloud gathers charge and the top portion of the cloud gathers the opposite charge, is still not thoroughly understood. Whatever the mechanism, though, a charge separation definitely exists and can lead to electrostatic discharge via cloud-to-cloud lightning and…