SearcharxivSearch

arXiv subjects

Steven W. Tarr

Publications and source records attributed to Steven W. Tarr.

2 recordsLinked to original sources

Reflecting to learn in a physics multimedia communication course

Science communication skills are considered essential learning objectives for undergraduate physics students. However, high enrollment and limited class resources present significant barriers to providing students ample opportunities to practice their formal presentation skills. We investigate the use of integrated critical reflection and peer evaluation activities in a physics senior seminar course both to improve student learning outcomes and to supplement highly restricted presentation time. Throughout the semester, each student delivers one 8-min multimedia presentation on either their research or an upper-division course topic. Following each presentation, audience members complete one of two randomly assigned peer evaluations: a treatment form that prompts critical reflection or a control form that does not. Each class period concludes with a short quiz on concepts presented in that day's presentations. We observe minimal differences in quiz scores between students in the control and treatment groups. Instead, we find that retention and transfer of presentation content correlate with certain metrics of presentation quality described in the Cognitive Theory of Multimedia Learning and with self-identified prior exposure to presentation topics.

physics.ed-ph

Probing hydrodynamic fluctuation-induced forces with an oscillating robot

We study the dynamics of an oscillating, free-floating robot that generates radially expanding gravity capillary waves at a fluid surface. In open water, the device does not self-propel; near a rigid boundary, it can be attracted or repelled. Visualization of the wave field dynamics reveals that when near a boundary, a complex interference of generated and reflected waves induces a wave amplitude fluctuation asymmetry. Attraction increases as wave frequency increases or robot-boundary separation decreases. Theory on confined gravity-capillary wave radiation dynamics developed by Hocking in the 1980s captures the observed parameter dependence due to these "Hocking fields." The flexibility of the robophysical system allows detailed characterization and analysis of locally generated nonequilibrium fluctuation-induced forces [M. Kardar and R. Golestanian, Rev. Mod. Phys. 71, 1233 (1999)].

physics.flu-dyn