摘要:

We begin by identifying the fascinating behavior of most of the thin, flexible magnets normally described as “refrigerator magnets.” Simple procedures are described that illustrate the intriguing physics of these magnets, which produce fields characterized by spatial variations that are quite abrupt compared to those of the more common ceramic magnets. A method is suggested for producing profiles of this spatial variation. The method is based on the use of magnetic field sensors that employ a novel phenomenon called giant magnetoresistance. After reviewing GMR and the sensors, we describe our field-mapping procedure and discuss the results.

ISSN:0031-921X    

DOI:10.1119/1.880045

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

A force diagram can be a “forceful” way to quickly get insight into a problem and prospects for a solution. A rigid application of some trivial rules can make a force diagram a more forceful tool.

ISSN:0031-921X    

DOI:10.1119/1.880046

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

This article describes an electrical analog to traditional projectile problems given in high school and introductory college classes. It also discusses the importance of stressing the understanding of physical laws and principles to students, and that the physics behind a problem is more important than being able to memorize and use various equations.

ISSN:0031-921X    

DOI:10.1119/1.880047

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

A practical air-supply system is described for laboratory apparatus such as air tracks and tables using regenerative blower technology. This flexible system is easily constructed and is comparable in cost to commercially available systems. Its advantages include low noise, high reliability, and low maintenance.

ISSN:0031-921X    

DOI:10.1119/1.880048

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

We discuss how the sound board, or sound blaster card, can be used as an analog-to-digital data logger in the student laboratory. As an example, we describe an inexpensive electro-cardiogram set-up that uses the line input of the sound board to digitize signals from a simple amplifier circuit.

ISSN:0031-921X    

DOI:10.1119/1.880049

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

In the long list of gifted Hungarian scientists and mathematicians active in the first half of this century, the name of Leo Szilárd rises to the top. This year we celebrate the centennial of his birth.

ISSN:0031-921X    

DOI:10.1119/1.880051

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

Fermat’s principle implies the well-known law of refraction of light. Our purpose is to show how one can give a simple justification, using only basic coordinate geometry, with the help of a graphics calculator and the Geometer’s Sketchpad®.

ISSN:0031-921X    

DOI:10.1119/1.880052

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

ISSN:0031-921X    

DOI:10.1119/1.1527511

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

In this article we will describe some large-scale macro-experiments in which the student is actually part of the experimental apparatus itself. This allows the student to actually feel physical phenomena for him/herself. This sensory experience helps students develop an intuitive understanding of physical phenomena, and it’s great fun!

ISSN:0031-921X    

DOI:10.1119/1.880053

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

A major hangup in solving physics problems often occurs when evaluating integrals. About 200 years ago, the great Gauss gave us an easy-to-computeandaccurate method for doing integrals. I give four examples, both familiar and not so familiar, that show the power of his method.

ISSN:0031-921X    

DOI:10.1119/1.880054

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP