Submitted Abstracts

1999 Fall Meeting of the Illinois and Iowa sections of the AAPT
Augustana College, Rock Island, Illinois

This file is automatically updated by the Web server after anyone submits an abstract by using the Online - Call for Papers. These abstracts will also appear in the detailed program for the meeting.


Papers to be Presented on Friday Afternoon

Paradox in Modern Physics?  Cecilia Vogel, Augustana College, Rock Island, IL 61201.  Undergraduate students learning modern physics often have a difficult time understanding -- or believing -- statements about the wave nature of particles and uncertainty. Even at the end of the course, they tend to still believe that the spread in a wave, and the uncertainty in position, momentum, etc. are just a matter of our not knowing the actual value or not having accurate enough equipment. In the hope of shattering that misconception, I have begun introducing my Modern Physics class to the Einstein-Podolski-Rosen paradox and the related experiments, which conflict with a purely classical view of uncertainty. The question remains whether this is important enough and effective enough to warrant inclusion in an already overcrowded syllabus.

A Wave Model of Hurricane Path Prediction. Ik-Ju Kang, Southern Illinois University - Edwardsville, Edwardsville, IL 62026-1654.  The requirement that the phases of incident and transmitted waves be matched yields the law of refraction, sin i / v = sin r / v'.  The velocity of the pressure wave is known to be proportional to the square root of the pressure.  Thus, one is lead to sin i / sin r = (p/p')0.5.  The angles i and r are the angles of incidence and refraction, measured from the normal to the isobaric line at the point of impact.  This model explains the total reflection, reversing the earlier path as well as grazing along the high pressure isobaric lines.

Backward Causation and Nonlocality in Quantum Mechanics. William R. Wharton, Wheaton College, Wheaton, IL 60187. Backward causation in which later events affect earlier events is formalized in a way consistent with Special Relativity and shown to restore locality to nonrelativistic quantum mechanics. The theory can explain the correlations of the EPR paradox without using hidden variables. It can solve Hardy's paradox by providing a realistic Lorentz-invariant interpretation. It also restores time-symmetry to microphysics. Quantum Mechanics is shown to have the right properties to allow for backward causation.

Common misconceptions require us to discuss time and causality in some detail. Time is a coordinate; one of four parameters which mark locations of events in our Universe. There is nothing inherent in temporal order which gives time a unique direction or flow, as the laws of physics are generally time-symmetric (and always CPT-symmetric). What's more, different reference frames will perceive different temporal orderings of the same space-time events. If the initial boundary conditions of the universe are defined as a "first cause", a causal order of all space-time events may be established -- an order which is independent of one's frame of reference. In other words, any space-time event may trace back a cause-effect path (or paths for multiple causes) to the Big Bang, and we assert that these paths should be the same in all reference frames. In the case of correlated space-like events we have two causal paths moving through each other, so that there is a causal symmetry between the events. The stochastic nature of QM makes this possible.     Continued

Reevaluating Huygens' Principle. Ken Smith, K.R. Roos, J.P. Kenny, Bradley University, Peoria, IL 61625. In the 300 years following its conception, the physical precept known as Huygens' Principle has steadily grown in acceptance and inclusion in academic texts. Huygens' original formulation, however, was based on conservation of energy and momentum in a luminiferous ether consisting of tightly packed, perfectly rigid particles. By removing this foundation, contemporary texts take Huygens' concepts out of their original context, rendering them inapplicable. Thus, a reevaluation of the meaning and consequences of Huygens' Principle is in order.

Determination of Interlayer Diffusion Parameters for Substrate Steps in Vicinal Epitaxial Systems. Brian Schupbach and K.R. Roos, Bradley University, Peoria, IL 61625. Vicinal metallic and semiconductor surfaces provide an experimental "playground" for controlling the formation of condensed structures on the atomic scale. Precise control and manipulation of condensed matter on the atomic scale requires quantitative knowledge of single atom diffusion parameters. We suggest a Scanning Probe Microscopy-based method for determining the important diffusion parameters for an epitaxial system. During epitaxial growth on a vicinal surface the size of the capture area, or denuded zone, near substrate steps is sensitive to the degree of single atom diffusion across terrace boundaries. Our Kinetic Monte Carlo simulation which realistically models epitaxial growth on a vicinal surface predicts an asymmetry in the denuded zones near ascending and descending terrace boundaries caused by restricted interlayer mass transport at the descending step. We compare the predictions of the model to Scanning Tunneling Microscopy images of low-temperature Ag/Ag(111) homoepitaxy, and extract the important parameters characterizing interlayer diffusion in this system.


Papers to be Presented on Saturday Morning

The New Illinois Teacher Certification Law, How Does It Affect Your Department?. Doug A. Franklin, Mark S. Boley, Western Illinois University, Macomb, IL 61455. Beginning next year, all current Illinois teaching certificates will expire every five years according to a new state law. In order for a teacher to renew their certificate, they must complete an approved professional development plan. As a result, Colleges and Universities must re-evaluate the preparation that their current teacher education students receive. In addition, programs for current teachers may need to be developed and/or revised. I will discuss how these changes may relate to physics departments throughout the state and look at the pros and cons involved in these changes.

Standards-based Reform in Physics Teacher Education. Carl J. Wenning, Illinois State University, Normal, IL 61790-4560. The new emphasis in the preparation of public school teachers is on accountability. Continual performance-based assessment of teacher candidates, and internal and external reviews of programs leading to licensure are fundamental components of state and national accreditation programs. The speaker, director of the NCATE/NSTA-accredited Physics Teacher Education program at Illinois State University, will describe significant reforms that are being implemented there as part of required ongoing assessment of both prospective teachers and their curriculum.

Imaging Near-Earth-Objects with the Principia TelescopeDavid A. Cornell and Catherine A. Hooper, Principia College, Elsah, IL 62028. The Minor Planet Center (MPC) of the International Astronomical Union posts on its Web site (http://cfa-www.harvard.edu/cfa/ps/mpc.html) updated orbital elements for many solar system objects, including members of the new class of asteroids called Near-Earth-Objects (NEOs).  We present examples of NEO images from Principia's 0.41-m f/10 RC reflector + CCD, along with methods of image processing and analysis, concluding with data submission to the MPC via e-mail.

Attempts at Introducing Group Learning in an Introductory Physics Laboratory. Frank Peterson, Iowa State University, Ames, IA 50011-3160. We have made several trials at structuring the operation of typical introductory laboratory experiments staffed by teaching assistants so that students work effectively in groups. Other goals of these efforts include a prompt evaluation of student learning, a grading system that fosters cooperation among students as well as performance and learning by students as individuals, significant feedback on student work during class, and access to exemplary solutions by students before they leave class. These trials and the results of these efforts will be described. This work is a continuation of some aspects of work described previously (F. C. Peterson, paper CE3, AAPT Announcer 29, 109 (1999)).

Temperature Distribution of Stress and Strain in MaterialsSariya R. Ahmad, Augustana College, Rock Island, IL 61201.  An applied force and temperature change on a long, hollow cylinder that is axially symmetric and functionally graded eventually causes a crack to form.  Concentrating on the temperature distribution of that cylinder at varying crack lengths for a given temperature on the external boundaries of that produces information to formulate conduction equations in polar coordinates.  Its solutions will describe the temperature distribution, therefore allowing predictions of various types of deformation at different temperatures and its behavior as the stress and temperature change are applied.  This research was done as part of the NSF-REU program at Hope College during the summer of 1999.

Using Magnetization and Hysteresis Measurements in the Education of Upper Level Physics Students. Mark S. Boley, Doug A. Franklin, Daniel K. Pratt, Matthew G. Walker, and Toni D. Sauncy, Western Illinois University, Macomb, IL 61455. Experiments have been performed on hollow ferromagnetic "high-speed" steel shafts, as well as on thin rings of maraging steel shrink-fitted onto solid stainless steel shafts, both for use as torque transducers in a variety of industrial and automotive applications. The primary objective of our studies thus far has been to successfully show a reproducible linear response of the field component (signal generated by the sensor) with applied torque in either direction. During these studies, it has been necessary to measure the initial magnetization curves and the hysteresis loops for the sensors after sequential heat treatment steps in order to have a more complete understanding of the physical processes that are essential to the development of reliable torque sensing devices. Consequently, we have found these types of measurements to be especially useful for upper level physics students who often leave undergraduate programs with little more than a sketchy textbook understanding of magnetism and magnetic properties. Not only do these students have the opportunity to perform the magnetization and hysteresis measurement processes themselves and develop the associated skills, but they also gain an improved physical understanding of the magnetic processes involved as their textbook learning is applied to the analysis of the data they obtain on "real-life" specimens.

Surveying Students' Conceptual Knowledge of Electricity and Magnetism. Curtis Hieggelke, Joliet Junior College, Joliet, IL 60431. The Conceptual Survey of Electricity and Magnetism (CSEM) was developed to survey students' knowledge about topics in electricity and magnetism. The survey is a 32 question, multiple-choice test that can be used as both a pretest and posttest. During four years of testing and refinement, the survey has been given to over 5,000 introductory physics students at 30 different institutions in one form or another. This talk will report the pre-instruction and post-instruction results for calculus-based and algebra/trigonometry-based students. From the analysis of student responses, a number of student difficulties in electricity and magnetism can be identified. Supported in part by NSF Grant DUE 9554683

TYC Physics Workshop Project '99 Update. Curtis Hieggelke, Joliet Junior College, Joliet, IL 60431. The TYC Physics Workshop Project started in 1991 with NSF support. Since then we have held 38 workshops/conferences at 17 different two-year college (TYC) sites in 12 states with over 800 participants (397 different ones). These participants represent 45 states plus two territories and 295 different TYCs in the nation. This paper will describe the recent (June 1999) 4th Introductory Physics Conference on Web and Internet-Connected Physics Courses, newly published Ranking Task Exercises in Physics (Prentice Hall), and our new focus on helping make improvement in physics courses that provide the core physics for advanced technology programs. Supported in part by NSF Grant DUE 9554683 and a new grant DUE 9950062 from the Advanced Technological Education (ATE) Program of the National Science Foundation.


Papers to be Presented on Saturday Morning or Afternoon

Quarknet 1999 in Iowa. Peter Bruecken and Jeff Dilks, Bettendorf High School, Bettendorf, IA, and Ames High School, Ames, IA .  The National Science Foundation and Department of Energy have sponsored a five year program called Quarknet.  Peter Bruecken and Jeff Dilks were the Iowa participants in this first year of the program.  These two high school teachers became part of a team of researchers and helped build two pre-production prototypes of Calorimeters for Compact Muon Solenoid scheduled to be online in 2005. We also went to CERN and tested and calibrated the prototypes. We will present a brief summary of our experiences and the planned continuation of the program in Iowa.

Measuring the Shape of Space Using the Cosmic Microwave Background Radiation. Troy Gobble and Keith Andrew, Eastern Illinois University, Charleston , IL 61920. The cosmic microwave background explorer, COBE satellite, collected data with a resolution of about eight degrees on the celestial sphere and detected relic anisotropies indicative of one of the earliest events in the universe, decoupling. Hidden in the correlations between these temperature fluctuations is the signature of the global shape or topology of the early universe. It is possible to calculate the temperature fluctuations as due to primeval adiabatic density fluctuations from the Sachs-Wolfe effect. Unlike the Einstein field equations these equations have a term that depends upon the topology of the universe. Here we investigate some of the spaces and how they effect the microwave background. The increase resolution provided by the Microwave Anisotropy Project and the Planck Probe will, by 2005, usher in a new era of experimental cosmology that can differentiate between different early universe dynamics, i.e. inflation vs. texture and different topologies, i.e. spherical vs. toroidal.

Investigating Student Difficulties With Concepts of Gravitation. Jack Dostal and David Meltzer, Iowa State University, Ames, IA 50011. Teaching the concept of gravity and the universal nature of gravitation in any physics or astronomy classroom can be difficult. Unlike subjects such as magnetism or optics, gravitation is difficult (or impossible, on astronomical scales) to demonstrate in a student laboratory. We have developed diagnostic instruments to identify students' initial concepts of gravitation. We are also developing materials to enable students to recognize incomplete and incompatible concepts and to strengthen their understanding of the nature of gravitation. The target audience for these materials is the typical population of introductory astronomy and physics courses - both science and nonscience majors. We will report diagnostic data, as well as data from class testing of the curricular materials.

Analyzing Linear and Angular Momentum Conservation in Digital Movies of Puck Collisions. J. C. Williamson, C. A. Kletzing, and R. O. Torres-Isea, University of Iowa, Iowa City, IA 52242. We describe a new undergraduate mechanics laboratory experiment that illustrates principles of linear and angular momentum conservation. Students observe that angular momentum is conserved in systems where the initial conditions involve only translational motions, and yet the final conditions include rotational motion. To do this, students make a digital movie of a two-object collision on an air table. One object has an asymmetric mass distribution and gains rotational kinetic energy as a result of the collision. Using their digital movie, students create a stroboscopic image of the two objects' trajectories and show that both linear and angular momentum are conserved to within a few percent, the limit of experimental uncertainty. Students also show that angular momentum conservation is independent of the choice of origin, that the center of mass of the asymmetric object follows a linear trajectory, and that the center of mass of the whole system follows a linear trajectory.

Available Outreach Programs and Workshops for High School Teachers and Students at Western Illinois University. V. Frohne, H. Hart, E. Hare, T. Sauncy, J. Rabchuck, Western Illinois University and Gary Wolber, Rock Island High School, Macomb and Rock Island, IL 61455. WIU is centrally located in a large rural area that contains many high schools with limited resources. The WIU Physics Dept. provides several outreach and support programs for local high school physics teachers and their students. During the summer, teachers are invited to participate in an intensive one-week workshop during which they learn to use computer-based laboratories, perform physics demonstrations, and build significant pieces of apparatus for use in their classrooms. During the school year, teachers may bring their entire physics class here to use our dedicated MBL-equipped lab. Experiments for high school students are available in mechanics, mechanical waves, sound, thermodynamics, electrostatics, holography, and radioactivity. Two of us (Sauncy and Rabchuck) have recently been awarded a grant for initiating a new outreach program in which WIU faculty take a "science road show" to area high schools. These programs will be described and items from the past year's Eisenhower workshop will be demonstrated. The workshops and instructional laboratory are funded by the Dwight D. Eisenhower Professional Development Program.


Papers to be Presented on Saturday Afternoon


Stability of Water in Small Cerenkov Detectors. Derek Strom, Augustana College, Rock Island, IL 61201, Hal Spinka, and Hank Glass, Fermilab. Secondary cosmic rays are zipping through our bodies at a rate of 100 per second. The highest energy cosmic rays, on the order of 1020 eV, are very rare and may contain some very interesting information about the origins of the Universe. The Pierre Auger Observatory in Argentina will have the largest detector array to study these intriguing particles. An important aspect of these detectors is the stability of the water inside the detector.  In this talk I will discuss the observatory and my involvement with it this past summer via work at Fermilab.

Active-learning curricula for thermodynamics in physics and chemistry. David E. Meltzer and Thomas J. Greenbowe, Iowa State University, Ames, IA 50011. We are developing and assessing new active-learning curricular materials for thermodynamics. These "guided inquiry" worksheets are being tested initially through use with introductory students in both physics and chemistry courses. I will discuss our preliminary investigations into students' learning difficulties with thermodynamic concepts, and the strategies we have employed to address these difficulties.

Building A-phi Scintillation Trigger Counters. James Raskowski, Northern Illinois University, DeKalb, IL 60115. The D0 collaboration at Fermilab is in the process of upgrading its muon detector, which should be completed next year. Students at Northern Illinois University have worked under the supervision of faculty members in various parts of the upgrade, including the building and testing of scintillation trigger counters. These counters are used in the timing (a few nanoseconds) of particles passing through them, aiding in triggering on muons. Construction of about one third of the total counters was completed last summer by students (the rest being done by IHEP in Russia), and testing has been proceeding since then. Counters are constructed out of bicron, a scintillating plastic, and then fitted with fibers which collect the light and carry it to a photomultiplier tube, where the particles are counted electronically. The first phase of testing indicates an efficiency level greater than 99.5%.


Newly Registered Papers

Great Physics Demos. David R. Renneke, Augustana, Rock Island, IL 61201. This is a test line.