January 2018 Issue, Volume 86, No. 1January 2018 Issue of American Journal of Physics


Revisiting the round bottom flask rainbow experiment

A popular demonstration experiment in optics uses a round-bottom flask filled with water to project a circular rainbow on a screen with a hole through which the flask is illuminated. We show how the vessel's wall shifts the first- and second-order bows towards each other and consequently reduces the width of Alexander's dark band. We address the challenge this introduces in observing Alexander's dark band, and explain the importance of a sufficient distance between the flask and the screen. The wall-effect also introduces a splitting of the bows that can easily be misinterpreted.




AJP and PER by Michael Wittmann, and Richard Price. DOI: 10.1119/1.5016042


One step beyond the electric dipole approximation: An experiment to observe the 5p→6p forbidden transition in atomic rubidium by F. Ponciano-Ojeda, S. Hernández-Gómez, C. Mojica-Casique, E. Ruiz-Martínez, and Flores-Mijangos. DOI: 10.1119/1.5006775

Revisiting the round bottom flask rainbow experiment by Markus Selmke, and Sarah Selmke. DOI: 10.1119/1.5008745

Harmonic oscillator thermal density matrix: First-order differential equations for the position representation by L. F. Barragán-Gil, and R. Walser. DOI: 10.1119/1.5008268

Demonstrating the conservation of angular momentum using spherical magnets by Johan Lindén, Joakim Slotte, and Kjell-Mikael Källman. DOI: 10.1119/1.5002548

Two famous results of Einstein derived from the Jarzynski equality by Fred Gittes. DOI: 10.1119/1.5003009

The electric field of a uniformly charged cubic shell by Kaitlin McCreery, and Henry Greenside. DOI: 10.1119/1.5009446

Recommendations for the use of notebooks in upper-division physics lab courses by Jacob T. Stanley, and H. J. Lewandowski. DOI: 10.1119/1.5001933

Computational Physics

Parallel programming with Easy Java Simulations by F. Esquembre, W. Christian, and M. Belloni. DOI: 10.1119/1.5012510

Physics Education Research

Race to improve student understanding of uncertainty: Using LEGO race cars in the physics lab by Maria Parappilly, Christopher Hassam, and Richard J. Woodman. DOI: 10.1119/1.5003812

Notes and Discussions

Coefficient of rolling friction - Lab experiment by Leonid Minkin, and Daniel Sikes. DOI: 10.1119/1.5011957


Out of the Shadow of a Giant: Hooke, Halley & the Birth of Science by Michael Nauenberg, American Journal of Physics 86. DOI: 10.1119/1.5012509


American Journal of Physics 86, 80 (2018). DOI: 10.1119/1.5016043

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