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Monday afternoon
shape their learning environments to be more representative of
students’ cultures and learning preferences. Physics instructors come
from different backgrounds than their students, and have difficulty
relating across cultures. Rather than focusing on boundaries, instruc-
tors can build upon shared classroom cultures that naturally develop.
The Cogenerative Mediation Process for Learning Environments
(CMPLE) is our formative intervention designed to help instructors
better engage with students by first gaining awareness of learning and
cultural issues. Then, instructors and students collaborate to design
and implement pedagogical changes that are connected to their
students’ backgrounds. Using CMPLE, instructors have the advantage
of knowing their methods are culturally relevant, through giving their
students meaningful and active roles. We highlight CMPLE’s use in a
high school honors physics class using the Modeling Instruction cur-
riculum, and a university course for pre-service elementary teachers
using the PET curriculum.
EG02:
8-8:30 p.m. Using Real Life Examples and
Manipulatives in Conceptual Physics
Invited – Virginia L. Hayes, 4226 S. Wabash Ave. Apt 2N, Chicago, IL
60653;
Students are motivated and excited when given real-life examples
when a topic is introduced in physics. When I work with students,
after a brief group discussion about real-life situations, the students
must connect the physics to the specific situations. There are other
times when students are given the key physics concepts and then are
required to create a real-life example that is relevant to the physics
concept. Students also use manipulatives to learn physics. Students are
given these tools along with the physics concepts and their definitions
to discuss the connection between the manipulatives and the terms.
There are two reasons for using these approaches to teach physics
to students in urban areas. Specifically, these techniques show the
students that physics is everywhere. The other benefit is to help stu-
dents see physics as relevant to them and for them to see themselves
as scientists. In this talk I will describe some of my experiences as a
science learner in the urban environment and how these experiences
inform my teaching.
Session EH: Innovative
Undergraduate Labs
Location: Salon 10
Sponsor: AAPT
Date: Monday, January 6
Time: 7:30–8:20 p.m.
Presider: Kendra Sibbernsen
EH01:
7:30-7:40 p.m. Exploring Fluorescence in
Homemade Candy Glass
Contributed – William R. Heffner, Lehigh University, Bethlehem, PA
18015;
Donald Wright III, Oakwood University
We present an investigation of the fluorescence observed in
homemade sugar glass (hard candy). Our home-built “Fluorescent
Monitoring System” utilized high-intensity LEDs for the excitation
and the student grade Ocean Optics Red Tide Spectrometer to resolve
the emission. The fluorescence was found to span between about 470
nm and 650 nm and the emission demonstrated a marked drop in in-
tensity for LED excitation below green. We measured the fluorescence
as a function of temperature and found it to decrease with increasing
temperature. The fluorescence also increased as the glass caramelized
(browned) with further heat treatment (cooking). Recent literature
has shown similar fluorescence in caramelized sugars to be due to the
production of carbon nanoparticles, and we propose the experiment
as a cross-disciplinary and open-ended one for an undergraduate lab
in physics, chemistry, or material science.
EH02:
7:40-7:50 p.m. A Laser Range Finder for the First-
Year Labs?
Contributed – Daniel E. Beeker, Indiana University, Bloomington, IN
47405;
An industrial laser range finder is evaluated for use in the first-year
physics labs. Performance is compared to a typical ultrasonic motion
detector.
EH03:
7:50-8 p.m. Magnetic Field Measurements
Contributed – Barbara Wolff-Reichert, TeachSpin, Inc., 2495 Main St.,
Buffalo, NY 14214-2153;
The existence of cheap commercial Hall effect sensors make it possible
for both high schools and colleges to create valuable experiments
where their students can measure the magnetic fields that they study
in their theoretical courses. This includes the fields from currents in a
long straight wire, a wire loop, and a Helmholtz pair of wire loops, as
well as their dependence on distance. Students can measure the on-
axis magnetic field dependence as a function of distance for a small
uniformly magnetized disk and discover the 1/r3 dependence. They
can determine the local Earth’s magnetic field. All these measure-
ments require the calibration of the sensor by the student. This in
itself, is a useful exercise in standards measurement. Something rarely
done in this computerized-instrument age.
EH04:
8-8:10 p.m. A Low-cost AFM for Undergraduate
Students
Contributed – Yingzi Li, Beijing University of Aeronautics and Astronau-
tics, Beijing, China; beijing beijing
Jin Li, Liwen Zhang, Jianqiang Qian, Hua Li, Beijing University of Aero-
nautics and Astronautics
Atomic force microscopy (AFM) is an import tool in nanotechnol-
ogy. This invention makes it possible to observe nanoscale surfaces
beyond the resolution limitation of light microscopy. In this paper
we developed a low-cost AFM with quartz tuning fork. It is easy for
undergraduate students to obtain deep insights into the nano world
with its simple operation and principle. Some parts of this device are
designed to be operated almost completely manually and it is a way
for student to understand the principle of AFM. This paper consists
of three parts. The principle of quartz tuning fork is shown first, then
mechanical structure and control system is introduced, and at last
the results of experiments done by students are shown. The compare
between these results and those that are obtained by commercial AFM
shows the validity and usability.
EH05:
8:10-8:20 p.m. SPAD – The World’s Cheapest Single
Photon Detector
Contributed – Jonathan F. Reichert, TeachSpin, Inc., 2495 Main St. Buf-
falo, NY 14214-2153 United States
Chances are you already have several of the world’s cheapest single
photon detectors in your parts junk drawer. For those “n-the-know”,
these are called Single Photon Avalanche Diodes (SPADs), but most
of us know them as LEDs. It turns out, if you reverse bias some LEDs
with about 25 volts DC, they exhibit avalanche breakdown when a vis-
ible photon strikes the sensitive area of the p-n junction. Studying this
breakdown phenomenon to confirm that it is a single photon event,
and that it obeys the Poissonian statistics for some experimental
parameters and not for others, is an important exercise for students.
One only needs an LED, an operational amplifier, associated power
supplies, oscilloscope, pulse counter, and a computer in order to study
these pulses. These may be the world’s cheapest single photon detec-
tors, but they are also probably the world’s most inefficient!
