Browsing the Journals

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

If you give multiple-choice tests, you may be interested in Heidi Wainscott’s analysis in the November 2016 issue of The Physics Teacher of the effect when students change their answers during an exam. In the same issue, the rotation of a can suspended near a jumping ring apparatus is a novel “twist” on this familiar demonstration. Another interesting surprise is Yaguo Ogawara’s proof that one gets improved traction by driving a front-wheel car backward up an icy slope than by driving forward. Finally, Hewitt’s Figuring Physics column concerns the difference in force when punching a heavyweight versus a lightweight boxer.

Two intriguing articles involve entropy in the January 2017 issue of the American Journal of Physics. The earth receives low-entropy energy from the sun and exhausts high-entropy energy to space; a paper on page 14 turns things around and imagines receiving energy from the cosmic background and exhausting it to a black hole instead. Then an article on page 23 devises a reversible way to exchange the temperatures of a hot and a cold body by splitting each of them into infinitesimal pieces and sequentially bringing those pieces into thermal contact.

Article 015009 in the January 2017 issue of Physics Education investigates numerically and experimentally the fastest descent along two connected inclined planes. I have written up a noncalculus analysis for the case when the second plane is horizontal (in response to the chocolate-bar challenge in Footnote 1 of this article) at https://www.usna.edu/Users/physics/mungan/_files/documents/Scholarship/DescentRampTrack.pdf. In the same issue, I also enjoyed the video analysis of a bullet fired underwater in article 015024.

The Indian Academy of Sciences journal Resonance often has useful review articles about topics in science and mathematics. Ones that caught my eye recently include a discussion of phase transitions in terms of the Ising model in the October 2016 issue, the temperature of gas in the interstellar medium in the November issue, and the inequalities among the arithmetic, geometric, and harmonic means (with applications and problems) in the December issue. These articles can be freely accessed at http://www.ias.ac.in/listing/issues/reso.

An article on page 1961 of the November 2016 issue of the Journal of Chemical Education presents an experimental method to measure the speed of sound in various gases. The Fourier transform is taken of the sound recorded while white noise is generated in an acoustic tube. The white noise is created by the expansion of gas rushing into the evacuated tube. The journal archives are at http://pubs.acs.org/loi/jceda8.

Article 020134 in Physical Review Physics Education Research discusses student facility with the divergence and curl in an intermediate-level undergraduate electromagnetism course.

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.