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July 26–30, 2014
Tuesday afternoon
medical imaging, material analysis, optics or even in space programs.
However, in a setup named Jablotron MX-10 it is ready for in-classroom
use. Unlike traditional detectors like Geiger tubes, the pixel detector offers
a real-time display, recognizes different particle types, and is able to show
particle traces. This poster will present a set of high school experiments
taking advantage of the chip abilities. Some examples of these experi-
ments are “Showing the statistical nature of radioactive decay”, “Studying
absorption of different particle types in materials” or “Natural background
radiation.”
*Sponsored by Dr. Stanley Micklavzina
F – Upper Division and Graduate
PST2F02: 5:45-6:30 p.m. Comparing Alternate Approaches to
Spacetime Diagrams
Poster – Roberto Salgado, University of Wisconsin La Crosse, 1725 State
St., La Crosse, WI 54601;
Tobias Nelson, University of Wisconsin La Crosse
We present a systematic survey of the various methods for drawing space-
time diagrams for special relativity. We study the Loedel, Brehme, Epstein,
and Minkowski diagrams. By considering how each method handles some
standard examples in Special Relativity, we identify the strengths and
weaknesses of each approach.
PST2F03: 5-5:45 p.m. Legendre Transforms for Dummies
Poster – Carl E. Mungan, U.S. Naval Academy, Annapolis, MD 21402-1363;
Legendre transforms appear in two places in a standard undergraduate
physics curriculum: (1) in classical mechanics when one switches from
Lagrangian to Hamiltonian dynamics, and (2) in thermodynamics to
motivate the connection between the internal energy, enthalpy, and Gibbs
and Helmholtz free energies. Both uses can be compactly motivated if the
Legendre transform is properly understood. Unfortunately, that transform
is often relegated to a footnote in a textbook, or worse is presented as a
complicated mathematical procedure. In this poster, I simplify the idea to
the point that the Legendre transform can be elegantly presented in class
in a sensible and accessible manner. In a nutshell, a Legendre transform
simply changes the independent variables in a function of two variables by
application of the product rule.
PST2F04: 5:45-6:30 p.m. Ongoing Validation of an Upper-division
Electrodynamics Conceptual Assessment Tool
Poster – Qing Xu Ryan, University of Colorado, Boulder, 390 UCB, Boulder,
CO 80309;
Cecilia Astolfi, Charles Baily, University of St Andrews
Steven Pollock, University of Colorado, Boulder
As part of an ongoing project to investigate student learning in upper-
division electrodynamics (E&M II), the PER research group at CU Boulder
has developed a tool to assess student conceptual understanding (the CUR-
rENT: Colorado UppeR-division ElectrodyNamics Test). This instrument is
motivated in part by our faculty-consensus learning goals and can serve to
measure the effectiveness of transformed pedagogy. In this poster, we pres-
ent measures of the validity and reliability of the instrument and scoring
rubric. These include expert validation and student interviews, inter-rater
reliability measures, and classical test statistics. This work is supported by
the University of Colorado and NSF-CCLI grant #1023208.
PST2F05: 5-5:45 p.m. Coupled Multiple-response vs
Free-response Formats in Upper-division Conceptual
Assessment
Poster – Bethany R. Wilcox, University of Colorado Boulder, 2510 Taft Dr.
Unit 213, Boulder, CO 80302;
Steven Pollock, University of Colorado Boulder
Free-response conceptual assessments, like the Colorado Upper-division
PST2E03: 5-5:45 p.m. Quality Education and Quality Entertain-
ment at HarvardX
Poster – Colin M. Fredericks, Harvard, 42 Rawson Road, Arlington, MA
02474;
In-classroom demonstrations and labs are great for hands-on experience,
and a lot of fun for students. Online courses need their own equivalents,
and there is no shortage of options. This poster presents some of the fun
stuff we’re building into our courses at HarvardX.
PST2E04: 5:45-6:30 p.m. The Effect of Online Lecture on
Performance in a Physics Class
Poster – John C. Stewart, University of Arkansas, Physics Building, Fayette-
ville, AR 72701;
This poster will examine the difference in student performance between
students attending lecture in person and students choosing to watch the
lecture on video as part of an online class. The option to watch the lecture
on video was implemented mid-semester in fall 2012 so that the per-
formance of the same set of students could be compared. A fully online
lecture section was introduced in spring 2013. Higher than expected
withdrawal rates have been experienced in the online sections of the class.
These will be examined in the context of the historical performance of the
class, the demographics of the students, and their motivation for enrolling
in the online experience. Differences in time-on-task for online and face-
to-face students will also be presented.
PST2E05: 5-5:45 p.m. The Physics of Smart Phone Sensors
Poster – Al J. Adams, University of Arkansas at Little Rock, 2801 South Uni-
versity Ave., Little Rock, AR 72204-1099;
Mobile devices today are powerful measurement systems and most of
the onboard transducers are designed to measure the very parameters of
interest to physicists and physics teachers. These include linear accelera-
tion, angular velocity, magnetic field, light and sound levels, and imaging
and video-recording capability. In order to use these portable measure-
ment systems most effectively in a teaching environment it is important for
those designing teaching and learning activities to understand the physics
behind their operation and the nature of their electronic output. I have
begun to research the design and operation of the sensors being used in
smartphones. Much to my surprise the basic physics behind them can be
found in most introductory physics texts; smartphone sensors provide a
timely illustration of physics principles, one of immediate interest to our
current student population.
PST2E06: 5:45-6:30 p.m. Tying Online Homework to the Book
While Keeping Costs Down
Poster – Andrew E. Pawl, University of Wisconsin-Platteville, 1 University
Plaza, Platteville, WI 53818-3099;
Paradoxically, the publisher-managed homework systems that accompany
textbooks are often constructed in a manner that actually discourages stu-
dents from engaging with the book. They are also expensive and offer sub-
scription models that do not always fit classroom logistics. In this poster, I
describe an alternative to commercial packages that simultaneously ties the
homework more closely to the book and lowers costs for the students. My
approach is explicitly intermediate between buying the publisher’s package
and the “do-it-yourself” option of coding up all the homework. It does
mean more work for me than when I was simply picking out problems
from the commercial package, but it is far less difficult than writing a com-
plete homework library of my own.
PST2E07: 5-5:45 p.m. Particle Physics Experiments for High
School Using Medipix/Timepix
Poster – Jan Koupil, IEAP, Czech Technical University, Prague Horská 3a/22
Prague, 12800 Czech Republic;
Vladimír Vícha, IEAP, Czech Technical University
The Medipix/Timepix chip developed by CERN is usually being used in
