A loop-the-loop experiment usually involves a ball rolling around a vertical loop. A different version of the experiment is described where a nut was allowed to slide around a vertical loop. In both experiments there is a large decrease in kinetic energy when the ball or the nut first enters the loop.

An alternative method for obtaining analytical solutions of the time-independent Schrödinger equation (TISE) is developed and applied to 1-dimensional model quantum systems of interest in atomic and molecular physics. The method is based on proposing a wave function that is a product of two functions, one of them an integrating factor. The…

In this article, we will present the HEC BB bag, a simple but elegant model originally invented to help students imagine how air molecules move around in vacuum. The HEC BB bag is made by packing 20 to 30 BBs in a resealable plastic bag of several tens of square centimeters (see Fig. 1). When inflated fully via a straw, the volume of the bag is…

This paper contributes to understanding the effects of research governance on global scientific fields. Using a highly selective comparative analysis of four national governance contexts, we explore how governance arrangements influence the dynamics of global research fields. Our study provides insights into second-level governance effects, moving…

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…

Bounded by the statements of Feynman and Galileo, I describe certain tricks that can be useful for the teaching of physics. In particular, I describe the calculation of the center of mass (centroid) of an arc of circumference and a circular sector. For this purpose, I also use Pappus's theorems. An Appendix is available with Archimedes' method to…

The various aspects of projectile motion have been analyzed many times in this journal. As a sample, over the years, authors have investigated particular details of the path of a projectile and different situations for launching projectiles. Others have written about a nifty way to determine the maximum height of a projectile, finding the range of…

In high school, and also in introductory physics courses in higher levels of schooling, the law of universal gravitation of planets is introduced by postulating Johannes Kepler's three laws, and later Isaac Newton's law of the inverse of the square of the distance to the Sun. The justification of the laws is only achieved in advanced courses in…

Experimental results are presented concerning the motion of a ball that bounces up an incline a few times then bounces back down again. The number of bounces up the incline is typically small since the speed of the ball in a direction parallel to the incline decreases rapidly, not only during each bounce but also while the ball is in the air. The…

From my home on the west bank of the Columbia River in Richland, Washington (46.3°N latitude), I have an unobstructed view of the sunrise along the east bank during an entire year. As a retirement project after a career of teaching and research in physics, I decided to take photographs of the sunrise for a year and, and at the same time, carry out…

About 30 years ago I taught a series of summer enrichment programs for high school physics teachers, using funding from the Howard Hughes Medical Institutes. I deliberately chose teachers from smaller cities and towns who were unlikely to have contact with other physics teachers. One of my more interesting teachers came from a rural area in a far…

The standing vertical jump (SVJ) is a classical topic in Newtonian mechanics (Fig. 1). Although the topic has also been treated by others (other terms used are "standing high jump" or "squat jump"), the present paper shows how a smartphone can be used to capture video of a jump and determine the jump height. A crucial…

In the movie Gravity, American astronaut and scientist Dr. Stone (Sandra Bullock) is on a spacewalk when tragedy suddenly strikes. An ever-increasing field of debris caused by a destroyed spy satellite damages the Hubble and Space Shuttle and quickly wipes out their mission. Dr. Stone spends the rest of the movie trying to find a ride back home.

This study proposes methods of reporting results of physics conceptual evaluations that more fully characterize the range of outcomes experienced by students with differing levels of prior preparation, allowing for more meaningful comparison of the outcomes of educational interventions within and across institutions. Factors leading to variation…

It is beneficial for quantum mechanics students to have a unified understanding of eigentheory concepts, so they can recognize the shared structure of mathematized phenomena from the different quantum mechanical systems of spin, energy, or position and recognize those as instantiations of the same overarching concept. Quantum mechanics instructors…