129
July 26–30, 2014
Wednesday morning
Session FE: Magnetism and Thermal
Labs, Beyond First Year
Location: Tate Lab 133
Sponsor: Committee on Laboratories
Co-Sponsor: Committee on Apparatus
Date: Wednesday, July 30
Time: 8:30–10:20 a.m.
Presider: Gabe Spalding
FE01:
8:30-9 a.m. Magnetotransport Experiments in the
Advanced Undergraduate Lab
Invited – E. Dan Dahlberg, University of Minnesota, School of Physics and
Astronomy, Minneapolis, MN 55455-0213;
Resistivity and magnetotransport experiments performed on magnetic
materials are ideal for teaching students aspects of both condensed matter
physics and experimental techniques. An added benefit is room tempera-
ture resistivity and magnetotransport measurements on thin magnetic
films are relatively easy to perform in an undergraduate laboratory. In this
talk I will discuss the preparation of samples, the experimental equipment
and techniques required for accumulation of the data and the data analysis.
For the magnetoresistance data the focus will be on the anisotropic mag-
netoresistance which requires only modest magnetic fields, on the order of
0.01T. With larger fields the extraordinary Hall effect can be investigated
(on the order of 0.7T required for Ni; larger fields required for Co and Fe).
An added physics bonus is temperature-dependent measurements of the
resistivity and the magnetotransport properties of the films.
FE02:
9-9:30 a.m. Improving the Quantification of Brownian
Motion
Invited – Ashley Carter, Amherst College, Merrill Science Center, Amherst,
MA 01002-5000;
Brownian motion experiments have become a staple in the undergraduate
advanced laboratory as a means to measure the Boltzmann constant or to
prove the atomic nature of matter. Yet, quantification of these experiments
is difficult. Typical errors can easily be 10-15% and often students will
produce measurements that are off by a couple orders of magnitude! In this
talk I will discuss the individual sources of error in the experiment: sam-
pling error, uncertainty in the diffusion coefficient, tracking error, vibra-
tion, and microscope drift. I will show you what sorts of error you should
expect to get in your experiments and how you can get students to model
that error computationally. Finally, I will describe some quick solutions
that have allowed students in my lab to reduce their errors to less than 1%.
FE03:
9:30-10 a.m. Opportunities and Challenges Arising in
Advanced Experimental Physics Courses
Invited – Jonathan McCoy, 5800 Mayflower Hill, Waterville, ME 04901-8840;
Advanced experimental physics courses, aimed at junior and senior
majors, can substantially shift a student’s perception of the discipline as a
whole. In particular, by emphasizing open-ended, project-based learn-
ing opportunities, these courses can provide a bridge between the core
curriculum and the exciting world of active research. At the same time,
these courses initiate departures from a familiar world of problem sets,
textbooks, and lab manuals that can be challenging for students. In this
presentation I will use a newly developed Experimental Soft Matter course,
taught at Colby College during the spring semester of this year, to explore
the opportunities and challenges arising in advanced experimental physics
courses more generally.
FE04:
10-10:10 a.m. 2-D and 3-D Random Walk Simulations of
Stochastic Diffusion
Contributed – Bob Brazzle, Jefferson College, 2019 Brutus Ct., Fenton, MO
63026;
I will describe a physical Monte Carlo simulation using a number cube and
a lattice of concentric rings of tiled hexagons. At the basic level, it gives
students a concrete connection to the Statistical Mechanics concept of
stochastic diffusion. I will also present a simple algorithm that can be used
to set up a spreadsheet to track the evolving concentration of simulated
“particles” (in contrast with the physical simulation, which tracks a single
particle’s motion). Although setting up the spreadsheet involves only
elementary mathematics, it is robust enough to allow one to demonstrate
or “discover” Fick’s first Law, and a discretized version of the stochastic
diffusion equation. Upper level undergraduates could thus use the spread-
sheet to independently explore relevant advanced concepts (e.g. flux and
concentration gradient). My AJP paper (November, 2013) describes this
simulation as well as several extensions: lattices with different geometries
in two and three dimensions.
FE05:
10:10-10:20 a.m. A Simple DTA Apparatus to Study
Binary Phase Diagrams
Contributed – Herbert Jaeger, Miami University, Department of Physics,
Oxford, OH 45056;
Thermal analysis is a way to study a material’s behavior during heating or
cooling. Structural changes can be observed to occur either continuously,
or at a given temperature, and with a specific signature. Differential Ther-
mal Analysis, or DTA, is one of the most basic forms of thermal analysis.
A DTA apparatus records the temperature difference of a sample and a
reference material during heating and/or cooling. Deviation from a zero
or near-zero baseline indicates specific events, such as melting, oxidation,
dehydration, or decomposition, among others. In this talk a simple DTA
apparatus will be discussed that can be used to explore the phase diagram
of a simple binary alloy.
Session FF: PER: Modeling Student
Engagement
Location: Tate Lab 166
Sponsor: AAPT
Date: Wednesday, July 30
Time: 8:30–10:10 a.m.
Presider: Andrew Boudreaux
FF01:
8:30-8:40 a.m. Facilitating Discourse in the High School
Physics Classroom
Contributed – Scot A. Hovan, University of Minnesota, Minneapolis, MN
55417;
The Next Generation Science Standards (NGSS)
1
identify eight practices
as essential to science and engineering, and several of these emphasize the
role of students’ constructing explanations, engaging in argumentation,
and communicating scientific information. As a high school physics teach-
er using Modeling Instruction, this research will highlight one portion of
a self-study analyzing experiences facilitating discourse in an attempt to
move students closer to those practices espoused by the NGSS.
1. National Research Council (2012),
A Framework for k-12 science education: Prac-
tices, crosscutting concepts, and core ideas,
Committee on a Conceptual Framework
for New K-12 Science Education Standards. Board on Science Education, Division of
Behavioral and Social Sciences and Education (Washington, DC: National Academy
Press.)
FF02:
8:40-8:50 a.m. Analyzing Physics Students’ Interaction
Patterns in an ISLE Studio Class
Contributed – Binod Nainabasti, Florida International University, Miami, FL
33172;
Kamal Kadel, Celestena Williams, David T. Brookes, Florida International
University
Yuehai Yang, California State University, Chico
Students’ interactions can be an influential component of an interactive
learning environment. We analyze video data of students working together
