Potential difference measurements in the presence of a varying magnetic field

Abstract

NEW APPROACHES contents of the calorimeter. As a result. calculating an accurate latent heat value would not be possible, unless one were to measure the mass difference between the original and remaining contents during the vaporization stage. Two faxinating experiences came out of this project for our students. First, students were able to apply computer technology to a fairly standard experiment and develop it into a meaningful research project that integrated concepts from circuits and thermo-dynamics. Second. students were able to observe a physical phenomenon with their own eyes that is usually presented to them in textbooks only. Direct visual observation enables students to better understand physical phenomena and laws (Mokros and Tinker 1987, Linn and Songer 1991). which is why this experiment is such a valuable activity for a physics course. References Galloway 1 A and Wilson J F 1992 Measuring the mechanical equivalent of heat-electrically Phys Teacher 30 504-6 Linn M C and Songer N B 1991 Teaching thermodynamics to middle school students What are appropriate cognitive demands? J. Res. Sci. reaching 28 885-918 Mokros J R and Tinker R F 1987 The impact of microcomputer based labs on children's ability to interpret graphs J. Res. Sci. Teaching 24 369-83

Some Student Conceptions of Electromagnetic Induction

“…If the two students who used Ohm's Law have the same kind of conception as the first 10 students, then the overall proportion who appear to hold alternative conception 3 stands at 80%. This confusion between electrostatic potential difference and induced emf has been discussed at length by Lanzara and Zangara (1995). A similar explanation of this difference was provided by Halliday, Resnick, and Walker (2001).…”

“…1, adapted from a similar diagram by Lanzara and Zangara (1995). The coil is placed near to the middle of the long solenoid with its plane perpendicular to the solenoid.…”

An introduction to the vector potential

“…Our experimental arrangement is analogous to that described in an extremely stimulating paper [6] entitled: 'What do "voltmeters" measure? : Faraday law in a multiply connected region', and in another article [7] which expands on some aspects of the previous one. We have adopted the same experimental configuration so that the content of the present paper should be better discussed after a careful presentation of Romer's consideration.…”

Symmetry and Voltmeters

“…This experiment and its variations make engaging demonstrations, and are the subject of many articles in this journal 1-10 and elsewhere. [11][12][13][14] At first, the fact that the two voltmeters give different readings is startling. 15 A quick way to understand this result is to consider symmetry under rotations and reflections.…”