Carl Mungan, United States Naval Academy
mungan@usna.edu

Alex Small has a practical review of lens aberrations for nonexperts on page 487 of the July 2018 issue of the American Journal of Physics (http://aapt.scitation.org/journal/ajp). In the September issue, Seung Ki Baek models the breaking of a pulled horizontal chain anchored to a wall at the other end as a function of the rate at which the force is applied; it is similar to the classic demonstration of pulling slowly or jerking the string connected to a hanging “inertia” ball. Finally, an article on page 733 of the October issue presents experiments and theory that help explain the flipping of a water bottle and of a plastic can of tennis balls in the air such that they land upright on a table.

Ker Liang Goh neatly explains how one can tell whether or not an extended body is in mechanical equilibrium when subject to three nonparallel but coplanar forces on page 384 of the September 2018 issue of The Physics Teacher (http://aapt.scitation.org/journal/pte).

Article 055101 in the September 2018 issue of the European Journal of Physics considers a “thermal bandage” toy model which is a 2D generalization of a classic problem by Charles Kittel useful as a student exercise in setting up and manipulating the partition function. Article 055203 in the same issue quantitatively analyzes a dc electric motor to find its angular speed and power as a function of time including back emf and load. The journal is online starting at http://iopscience.iop.org/journalList.

Article 2301 in the June 2018 issue of the Latin-American Journal of Physics Education (http://www.lajpe.org/) attempts to define the term “thermodynamics” at the beginning of an introductory course or unit on the subject. I agree a definition is tricky; mine is “The study of how materials change when energy (by heat, pressure, electromagnetic fields, mass transport, etc) is added to or removed from them.”

The September 2018 issue of Resonance has a five-page biography of Arthur Holly Compton, along with a reprint of the 1923 Physical Review paper on his eponymous scattering effect. These articles can be freely accessed at http://www.ias.ac.in/listing/issues/reso.

A document camera, 3D glasses, and smartphone screen can be used to construct a polarimeter to analyze a sucrose solution, as explained on page 837 of the May 2018 issue of the Journal of Chemical Education. Page 1668 of the September issue presents a historical account of the name and ideas behind shot noise. The journal archives are at http://pubs.acs.org/loi/jceda8.

Article 010144 in Physical Review Physics Education Research at https://journals.aps.org/prper/pdf/10.1103/PhysRevPhysEducRes.14.010144 discusses undergraduate student beliefs about the curvature of the universe, such as that it must be spherical.

Disclaimer – The articles and opinion pieces found in this issue of the APS Forum on Education Newsletter are not peer refereed and represent solely the views of the authors and not necessarily the views of the APS.