When asked to explain the Galilean non-invariance of classical electromagnetism on the basis of pre-relativistic considerations alone, students--and sometimes their teachers too--may face an impasse. Indeed, they often argue that a pre-relativistic physicist could most obviously have provided the explanation "at a glance", on the basis of the…

Employing Bohr's quantum theory, the author deduces three limits, which correspond to the magnetic fields of white dwarfs, neutron stars and the strongest in the universe. The author discusses the possible origins of magnetic fields due to collapse of stars, which produces a magnetic field of 10[superscript 8] T. Although the complete analysis…

A system of two magnets hung from two vertical springs and oscillating in the hollows of a pair of coils connected in series is a new, interesting and useful example of coupled oscillators. The electromagnetically coupled oscillations of these oscillators are experimentally and theoretically studied. Its coupling is electromagnetic instead of…

Experiments with an electric motor provide good opportunity to demonstrate some basic laws of electricity and magnetism. The aim of the experiments with a low-power dc motor is to show how the motor approaches its steady rotation and how its torque, mechanical power and efficiency depend on the rotation velocity. The tight relationship between the…

Two possible topical approaches that have been applied to teaching an upper-division undergraduate electrical engineering applied electromagnetics course are presented. Each approach was applied to one of two offerings of the course, taught in different semesters. In either case, the course includes the study of electromagnetic theory and…

Exploring the critical role of school choice in the future of education reform, the Education Choice and Competition Index (ECCI) is an interactive web application that scores large school districts based on thirteen categories of policy and practice relevant to choice. The intent of the ECCI is to: create public awareness of the differences among…

Beginning in the 1970s, many school US school districts reallocated their already scarce resources from local schools to specially created magnet schools. Many of these magnet schools have some sort of entrance exam, portfolio, or audition requirement that students must pass in order to gain admission. These selective magnet schools are predicated…

Magnet schools make up the largest system of choice in the U.S. They were originally conceived to accomplish the twin goals of innovation and integration. Over the years, however, the integrative mission of magnet programs has somewhat receded, particularly during the second Bush Administration. Meanwhile, political and financial support has…

Nationwide, magnet programs enroll more than twice the number of students served by charter schools, making them the most popular form of school choice. Across the U.S., over 1.5 million U.S. children attend magnet schools. In Miami-Dade County Public Schools, over 42,000 students are enrolled in magnet programs. The bulk of this report focuses on…

To achieve President Obama's stated goal of making increased expectations for students and schools a national priority, the administration has designed a blueprint for a reenvisioned federal role in education through the reauthorization of the "Elementary and Secondary Education Act" ("ESEA"). The new "ESEA" will…

This article describes a technique for measuring the magnetic field inside a long solenoid using computer data logging. This is a new approach to a standard student practical. The design and construction of the sensors is described; they significantly reduce the cost of the apparatus. The approach of the practical is for the students to…

The simple pendulum has long been used to measure "g", the acceleration due to gravity, with a precision of a few percent. Achieving agreement with the accepted value of less than 1% is feasible in the high school laboratory, though it requires some care. The precision of the measurement is bound by how accurately the period and the pendulum…

We examine a set of academic and social outcomes in 9th grade, comparing middle school attendees with those who attended K-8 schools. Previous research with these data has shown that there are few differences in 8th-grade outcomes by school type. Here we extend these findings to determine whether school form influences student outcomes in the…

A rotating magnetic field is the basis for the transformation of electrical energy to mechanical energy. School experiments on the rotating magnetic field are rare since they require the use of specially prepared mechanical setups and/or relatively large, three-phase power supplies to achieve strong magnetic fields. This paper proposes several…

We describe a simple experiment demonstrating the variation in magnitude of a magnetic field with distance. The method described requires only an ordinary magnetic compass and a permanent magnet. The proposed graphical analysis illustrates a unique method for deducing a general rule of magnetostatics. (Contains 1 table and 6 figures.)