2005-11-01

Wittmann, Morgan, and Bao on energy loss in tunneling

M.C. Wittmann, J.T. Morgan, and L. Bao
Addressing student models of energy loss in quantum tunneling
European Journal of Physics 26, 939–950 (2005)

2005-08-31

Sayre MST: Resource activation

E.C. Sayre
Advanced Students' Resource Selection in Nearly-Novel Situations
Unpublished M.S.T. thesis, University of Maine, 2005

To better understand the processes of student learning, one of the primary goals of physics education research, researchers build cognitive models. In this thesis I expand and further detail the resources model, a knowledge-in-pieces model of cognition, through the use of two metaphors, maps and graphs.

Resources may be characterized as to type. Metacognitive resources can mediate and expand problem solving strategies and are in turn mediated by epistemological resources about the subject matter at hand. The four resources types - metacognitive, problem solving, epistemological, and content - are therefore deeply tangled.

Maps and graphs, complementary representations of the resources model, provide organizational structure and illustrate core properties of the model. Maps show which resources are relevant to a given situation. Graphs show how those resources can be connected to each other. Maps and graphs also lend language to the analysis of sense-making in nearly-novel situations.

A nearly-novel situation is one that forces students into an area outside of established conceptions – off the map - but still near many resources. Being near many resources means that students will have many opportunities to build graphs by linking resources together to help make sense of a new situation. Being outside of established conceptions means that students will not already have a pat explanation, and therefore will be forced to make sense on-the-fly.

The physics of diode design is an ideal nearly-novel situation in which to study epistemology and metacognition in upper-level physics students: rich in physics ideas, not mathematically complex, and understudied by the population. Because upper-level physics students are a small population, the statistical approach of data analysis is not used. Instead, data are presented in terms of trends and supporting stories.

Through clinical interviews and an iterative survey, students are first questioned about the functions of diodes in circuits, then asked to design a diode given a charge source. The diode identification question serves a necessary orienting purpose for the subsequent design questions, though it does not predict design capability for this population. Following their design, students are asked a series of demographic and teaching questions intended to both probe their previous studies of diodes and suggest possible effects to consider in a redesign of their diodes. Students may then redesign their diode.

Diode designs followed two basic schemes: true diodes and protodiodes. Nine of twenty-five respondents were incapable of designing diodes. Non- designers usually indicated that they could not remember how to design a diode, despite having never studied diode construction. Epistemologically, these students appear to use knowledge-as-rememberable to the exclusion of knowledge-as-derivable in this context.

We find two constraints on successful reasoning in nearly-novel situations. To see a situation as nearly-novel, students must both be familiar with the necessary material and see that material as relevant to the situation at hand - the material must seem to be cognitively nearby. Furthermore, to reason successfully in a nearly-novel situation, the epistemological resource knowledge-as-derivable must not be blocked from activating.

Menchen MST: Sound propagation and resonance

K. VP. Menchen
Investigations of Student Understanding of Sound Propagation and Resonance
Unpublished M.S.T. thesis, University of Maine, 2005

This writing discusses the process of determining what students think about the phenomena of sound propagation and resonance using written pretests and interviews and then developing a curriculum based on analysis of student responses. We found that students and teachers alike generally have a difficult time understanding both propagation and resonance, which are foundational in this supposedly “simple science” of sound. The major difficulty that students encounter is their intuition that an object must vibrate only at its natural resonant frequency. Students tend not to put many limits on this rule, and misapply it to all kinds of situations, especially in propagation and resonance. Another common thought that students hold to is that a sound’s frequency will be altered by traveling through various materials. The research revealed many other misconceptions. Sound is a topic generally covered only at elementary school levels, and it is referred to in upper-level courses, as something already well understood to explain ideas pertaining to waves or quantum physics. It is disturbing to observe so many misconceptions in understanding sound, considering the accessibility of this topic.

The curriculum presented here has been developed and informed by these ideas to better help college-level students (mostly education majors) learn by taking into consideration their current understanding of how sound works. We target education majors primarily because they will presumably be passing along this information to the largest audience. The curriculum is used in a guided-inquiry, lab-based course that explores the fundamentals of physics in a hands-on style. My work starts with a preliminary version of curriculum, which has been improved over the past two years to more effectively teach students. The curriculum portions I’ve worked most on have been those that address the effects on the frequency of a sound with respect to resonance and propagation. Specifically, the curriculum has fostered improvements in students’ separation of the ideas of frequency and amplitude; their language when describing the motion of these two concepts; and improved but not flawless understanding of propagation, and how the medium affects the sound passing through. While improvements have been made, there are yet more developments to apply to the sections on propagation, as we continue to understand just what students struggle with.

2005-08-20

Odell MST: Conservation of Mass/Energy

Jessica Odell
Student Understanding of Conservation of Mass/Energy in Introductory University Science Courses
Unpublished M.S.T. thesis, August 2005

In the Fall of 2004, student understanding of conservation of energy and mass was measured in four introductory-level science courses (biology, chemistry, earth science, and physics) at the University of Maine. Each course fulfilled one semester of the University’s general science education requirement. A 20 question, multiple-choice survey was administered to students in the four courses, in a pre/post-test format. Ten questions on the survey involved the application of the concepts of conservation of energy and mass in either local or system-wide situations, and were scored to calculate gain.

Sub-groups of students were compiled by taking only those who were taking one science course during the semester. Average normalized gain was calculated for each sub-group to allow for comparison between courses. Students taking the biology course had significant improvement in the systems applications, while students taking the chemistry course showed improvement on the local-level applications. Students enrolled concurrently in biology and chemistry showed significant gains in both subsets of the survey, with an overall gain greater than students enrolled in each of the courses individually. Students enrolled in the physics course showed no significant gains, while earth science students showed significant negative gain on the local applications subset of the survey. The results suggest that there is a difference between the introductory courses that fulfill the University of Maine’s general science education requirement, in terms of improving student understanding of conservation of energy and mass.

2005-06-01

Kanim and Thompson on magnetic field viewing cards

S. Kanim, J.R. Thompson
Magnetic Field Viewing Cards
The Physics Teacher, 43:6, 355–359 (2005)

2005-05-01

Redish and Wittmann on PER

E.F.Redish, and M.C. Wittmann,
Twenty Questions for PER
Physics Education Research Conference Proceedings, 2004, edited by J. Marx, S. Franklin, and P. Heron, AIP Conference Proceedings (2005)