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Monday afternoon
tal data. Additional advanced experiments will be summarized.
PST1B19: 8:30-9:15 p.m. Visualization of Vibrating Systems
Using a Scanning Laser Doppler Vibrometer
Poster – Thomas M. Huber, Gustauvs Adolphus College, St Peter, MN 56082;
Peter Crady, Edward Kluender, Gustavus Adolphus College
A scanning laser vibrometer uses the Doppler shift of reflected light from
an object to obtain incredibly precise visualizations of the deflection shape
of vibrating objects. This system has been utilized to obtain insights about
a wide variety of physical systems. We will describe measurements where
the non-contact ultrasound radiation force excited vibrations of systems
ranging from a microcantilever to the face of an acoustic guitar. Other
measurements demonstrated that the reed in a reed organ pipe experiences
accelerations in excess of 4000 g’s. Visualization of the vibration of beakers
excited by a speaker allowed better understanding of how they break. The
vibrometer even enabled measurement of the sound waves traveling in
tubes or emitted from ultrasonic ranger. Videos and curriculum guides
have been produced to allow these visualizations to be utilized in classes.
This project has been supported by NSF Grants: 0959858, 0900197, and
1300591.
PST1B20: 9:15-10 p.m. Musical Intervals and Scales
Poster – Michael C. LoPresto, Henry Ford Community College, Dearborn, MI
48128;
Classroom demonstrations and laboratory experiments on superposition
of waves and Fourier analysis, and a student laboratory on analysis of the
equal-tempered musical both scale, both based on research on the percep-
tion of musical intervals by the human ear.
PST1B21: 8:30-9:15 p.m. Physics Models & Experimental Errors
Poster – Daniel M. Crowe, Loudoun County Public Schools, Academy of Sci-
ence, 21326 Augusta Dr., Sterling, VA 20164;
For the past several years, I have explicitly taught my students how to
describe the physical and mathematical models used in textbook problems
and the analysis of experiments. I have also explicitly taught my students
how to use the physical models used to analyze experiments to identify
sources of experimental error, especially systematic errors. I have also
described to my students the relationship between physics models and the
engineering concepts of tolerance and safety factor. I will describe specific
examples of how these concepts have been used in my AP Physics C:
Mechanics classes.
PST1B22: 9:15-10 p.m. Measuring Musical Consonance and
Dissonance
Poster – Michael C. LoPresto, Henry Ford Community College, Dearborn, MI
48128;
An overview of methods of quantifying the sensations of musical con-
sonance and dissonance compared to the judgment of human subjects
and the application of this research in several classroom activities on the
subject.
PST1B23: 8:30-9:15 p.m. More Than g, or No g
Poster – Glenda Denicolo, Suffolk County Community College, Port Jefferson
Station, NY 11776;
We have carried out a study of the virtues and pitfalls of video analysis
applied to two different experiments that measure acceleration: 1) falling
at a faster rate than g (hinged board where free end accelerates faster than
g when falling), and 2) falling with no acceleration (magnet rolling down
a metal ramp with terminal velocity). Video analysis has been widely used
in experiment-based project work in introductory mechanics, but it is not
straightforward to perform precise measurements with this technique. We
share our experiences in preparing, recording, and performing these video
indicating and recording the precession of the pendulum. This presentation
shows different forms of drives that can be employed and discussed the
advantages of each, as well as some problems that are encountered when
working with Foucault pendula.
PST1B16: 9:15-10 p.m. The Magnetopause: Bringing Space
Physics Into a Junior Lab*
Poster – Jim Crumley, College of St. Benedict / St. John’s University, Col-
legeville, MN 56321-2000,
Ari Palczewski, Stephen Kaster
Undergraduate students often have minimal exposure to many subfields of
physics which are active areas of research. Space physics is an area that is
particularly difficult to expose students to since it builds off of another area
that most undergraduates see little of, plasma physics. The magnetopause
is a convenient entry point into space physics, since it can be modeled as
a pressure balance, which is a concept familiar from introductory physics.
We use the Earth’s magnetopause as the basis for a lab for junior physics
majors. In the lab students analyze results from a NASA MHD simulation
1
and data from several spacecraft. In this lab, not only are students exposed
to space physics, but they also develop their data analysis skills.
*This research was supported by an award from Research Corporation.
1. Simulation results have been provided by the Community Coordinated Modeling
Center
) at Goddard Space Flight Center through their
public Runs on Request system.
PST1B17: 8:30-9:15 p.m. Using Student’s t-scores to Teach
Measurement, Uncertainty, and Experimentation Skills
Poster – Natasha G. Holmes ,University of British Columbia, Vancouver, BC
V6T 1Z1 Canada,
D. A. Bonn, University of British Columbia
Many introductory physics labs ask students to conduct experiments to see
or experience physics concepts from class first hand. Students collect data
from these experiments and are expected to analyze the data to make sense
of the physics equations they’ve learned in class. In first year, however,
many students have little to no experience with the probabilistic nature
of data, measurement, and uncertainty and may also hold misconcep-
tions about these ideas. Without that understanding, there are significant
limitations to extracting physics concepts from the data and developing
experimentation skills. In a first-year physics lab at UBC, we have removed
the conceptual physics learning goals from the course and replaced them
exclusively with goals for learning data analysis and measurement skills.
This year in particular, we have introduced a tool analogous to the Stu-
dent’s t-test as a way to engage students in meaningful reflection of their
data and to promote iterative experimentation. This poster will present
some of these learning goals and associated teaching techniques, as well as
evidence of its success.
PST1B18: 9:15-10 p.m. Vacuum Systems for Scientific Modeling
Poster – Tom M. Christensen, University of Colorado at Colorado Springs,
1420 Austin Bluffs Parkway, Colorado Springs, CO 80918;
Marilyn Barger, Florida Advanced Technological Education Center
Raul Caretta, University of Minnesota
Richard Gilbert, University of South Florida
James Solomon, University of Dayton
Many high schools and universities have small vacuum systems that are
used primarily for demonstrations. We review here more advanced labora-
tory applications of vacuum systems that have been developed as part of
the annual AVS Science Educator’s Workshop.* An emphasis on scientific
modeling of exponential processes and non-ideal behavior of gasses can
give students a better understanding of real science and engineering. We
focus on two vacuum system experiments in which we connect theory,
model, and observations. The first experiment examines the pump down
characteristics of the vacuum system which is predicted to follow an expo-
nential behavior. The second examines Boyle’s law but demonstrates that
the ideal gas model is not obeyed allowing discussion of a polytropic model
and methods for determining the exponent in the model from experimen-
