A Simple Dynamics Experiment Based on Acoustic Emission

This paper describes a simple experiment well suited for an undergraduate course in mechanical measurements and/or dynamics, in which physical information is extracted from an acoustic emission signature. In the experiment, a ping–pong ball is dropped onto a hard table surface and the audio signal resulting from the ball–table impacts is recorded. The times between successive bounces, or “flight times”, are used to determine the height of the initial drop and the coefficient of restitution of the impact. The experiment prompts questions about modeling the dynamics of a simple impact problem, including the use of the coefficient of restitution and the importance of accounting for aerodynamic effects

Galileo\u27s Contribution to Mechanics

Asim Gangopadhyaya writes about Galileo\u27s contributions to mechanics and physics in this chapter in Where Have All the Heavens Gone? Galileo\u27s Letter to the Grand Duchess Christina edited by John P. McCarthy and Edmondo F. Lupieri

Geographic Potential Surfaces

The attempt is made to trace the development of the surface potential with particular reference to the social sciences, especially geography. The geographic potential is derived from Newton\u27s law, F = GMm/d and is mathematically expressed and explained. The formula for the ,r potential at a single point or area, j, is ;~1(P;•P) / d;; \u27• Minnesota population potential for 1960 and 1930, and 1960 Minnesota income potentials have been calculated and mopped. The Twin Cities possess the peak potential for all three variables. Of prime importance to the understanding of geographic potentials is a knowledge of the underlying assumptions and limitations, of which there are many. In spite of these, the potential is of particular value in presenting on ideal model to which reality con be compared

CONTEMPORARY COSMOLOGY AS A CASE STUDY IN SCIENTIFIC METHODOLOGY

This thesis examines two recent research projects in cosmology with the aim of presenting them as a case study of the use of evidence in science. Descriptions of scientific reasoning commonly use language reminiscent of simple hypothetico-deductive methodology. However, a number of philosophers of science have argued that this model of scientific reasoning is inadequate. In particular, recent work has looked to the methodology of Isaac Newton for an addition to the standard hypothetico-deductive account. This methodology seeks to deliver a richer notion of empirical success through providing warrant for scientific claims on the basis of the ability of a theory to deliver agreeing measurements of its theoretical parameters from diverse and independent sources. One aspect of recent work in cosmology is the introduction of specific measurements of a positive value of the cosmological constant, A, a theoretical parameter that, prior to recent results, most cosmologists either ignored or assumed to be set at zero. This thesis claims that, in accordance with Newton\u27s methodology, it is through the use of this richer notion of empirical success that the current research provides empirical support for the inclusion of the parameter and for the standard cosmological model in general. The thesis examines the core of the course of cosmological reasoning regarding the relationship between observation and the mass-energy density parameters of the universe. Following an introductory chapter, Chapter Two reviews the standard cosmological model prior to the recent work on A, with a focus on the use of agreeing measurements in this research. Chapter Three reviews recent cosmological research on type la supemovae and the use of these events to produce measurements of cosmological iii produce measurements of cosmological parameters. Chapter Five reviews the use of the agreement in the measurements produced by these theories and the nature of the empirical support that this agreement delivers to the standard cosmological model against systematic error and against alternative theories that may be potential rivals of the standard cosmological model

Complex Realities, Simple Beauties: Interactions between the Development of Physics Ideas and Western Civilization, from Ancient Times to the Late Nineteenth Century

An instructive text covering the history of Physics concepts within the western tradition. It begins with a brief history of the human species, including discussions of food-gathering technology, early settlements, and the development of culture. It continues on to trace the development of human intellectual culture through ancient history and European history, charting a course through Mesopotamian, Egyptian, Greek, and Arabic mathematical and scientific contributions. Much of the book examines the interaction of science with historical factors such as war and rule changes. It challenges readers to think about ways of knowing and the process of developing systematic knowledge

A Middle School Standards-based Science Curriculum Handbook

As teachers implement the National Science Education Standards (1996) many must change the instructional methods they have used throughout their careers. This handbook will assist teachers to be facilitators in inquiry-based classrooms. The nine units of this handbook have been implemented for three years in an eighth grade classroom and have been used and modified by three different teachers to meet their own needs. The units in this handbook were chosen by MSAD #3, Unity, Maine, to reflect the curriculum requirements of The State of Maine Learning Results (1997). Included in this handbook are physics units covering motion, forces, work, and energy, with an in-depth study of electromagnetic and chemical energy, and a unit in human anatomy and physiology. An emphasis is placed on teens and their health during the discussion of the systems of the body. This handbook relies on the mandate from Benchmarks for Science Literacy (1993) and National Science Education Standards (1996) for science education to be inquiry-based. Students must do science - which means students observe, collect, compare, hypothesize, experiment, interpret, classify, and communicate what they learn. Learning science becomes an active process of students interacting with materials and sharing conversations about their discoveries. The guided inquiries of this handbook reflect this recommendation. The classroom that follows this handbook will be an active classroom of engaged students exploring the tools and techniques of a scientist. The inquiry units in this handbook are a compilation of my classroom experiences and readings from the internet, workshops attendance, and textbooks gleanings. Every unit in this handbook is explained in full with the goals and objectives of the unit and an explanation of the pitfalls and strengths of each activity. The guided inquiries form the backbone of the units, but projects and presentations along with end-of-the-unit lab practicums form other forms of assessments. Throughout the set of nine units, there are ample opportunities for students to communicate their findings

A Comparison of Vertical Velocity Profiles from the Balloon Borne Sounding System and the 915/50 MHz Radar Wind Profiler/Radio Acoustic Sounding System to Parcel Theory at the ARM SGP Site

In this study we characterized vertical wind velocity profiles in the troposphere using the Atmospheric Radiation Measurement (ARM) equipment facility at the Southern Great Plains (SGP) site in Lamont OK established by the Department of Energy (DOE) and administered through Argonne National Laboratories (ANL). Using the Balloon Borne Radio Sonde (BBSS) system launched four times per day, we collected ambient temperature profiles and lapse rates from the period of June to September of 2001. Concurrently the Rass Radar Wind Profiler collected vertical wind speed data at 915 MHz continuously throughout this period. The BBSS data is visualized using a Skew-T atmospheric profile plot allowed calculations of the Convective Available Potential Energy (CAPE) by integrating from the fiducial saturated adiabatic lapse rate curve to the ambient temperature curve. From this we calculated the vertical velocity using ideal atmospheric parcel theory. In addition the linear Brunt-Väisälä convective parcel theory is compared to the Skew-T derived lapse rate velocities applied to the stable regime. A statistical comparison was made to characterize the condensation fraction associated with vertical winds at the topographically unique SGP location. Robustness of the comparison is tested using second, third and fourth order moments and by testing for a normal distribution of the deviations. We found that the χ2 = 0.889 for CAPE and RWP vertical velocities measured in the aggregate. This characterization matches the methodology used at a similar site in Darwin, Australia and was used as input for full scale three-dimensional modeling of the atmosphere over SGP. The CAPE derived vertical wind speed parameter was found to be 0.55 for the SGP site

Investigating Teachers\u27 Content Knowledge and Pedogogical Content Knowledge in a Middle School Physical Science Curriculum on Force and Motion

Teaching is a profession that requires the incorporation of many types of knowledge in order to create effective instructional experiences that promote student learning. Teachers need to blend their knowledge of the content with the methods for delivering that content and an understanding of their students\u27 thinking. With increasing concern in the United States over student achievement in science and mathematics, there is ongoing discussion about which elements of teacher knowledge most directly correlate with effective instruction. How do specific strands of teacher knowledge blend to influence student learning outcomes? This study explores the roles of teacher content knowledge (CK) and pedagogical content knowledge (PCK), particularly teacher knowledge of student ideas (KSI), in the context of a middle-school physical science curriculum on force and motion. The study takes place within the Maine Physical Sciences Partnership (MainePSP). The primary focus of the MainePSP is the professional development of physical science instructors in grades 6-9 via curriculum renewal using common instructional resources across multiple school districts in rural Maine. Teachers and their students were given multiple-choice assessment items to examine teachers’ CK as well as the learning gains of their students. To measure teacher KSI, teachers were additionally asked to predict if a significant portion of their students [\u3e10%) would select a multiple-choice option on a certain assessment item and to articulate student reasoning for selecting that choice. For both the CK and the KSI surveys, teacher performance varied widely, between 10% and 90% of the maximum score on each survey represented, with little to no correlation between CK and KSI scores. Overall results from the student assessment indicate that students come into the curriculum with incorrect ideas about force and motion, but are on par with comparable populations seen in the literature. Furthermore, there was little shift in student understanding of force and motion concepts after instruction of the curriculum. Additionally, teacher CK and KSI were not strong predictors of student performance when related to the narrow learning gains observed. We discuss possible factors to which this lack of correlation may be attributed, including the implementation process and elements of the curriculum itself, and also the resolution of the KSI instrument. Recommendations for future research are provided