ISSN:0002-9505    

DOI:10.1119/1.9830

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

The American Association of Physics Teachers conferred Distinguished Service Citations on six outstanding contributors to physics education: Bill G. Aldridge, Florissant Valley Community College; Stanley S. Ballard, University of Florida; Phillip R. Brieske, University of Wisconsin, Superior; Wilbur V. Johnson, Central Washington State College; Walter E. Massey, Brown University; Lester G. Paldy, State University of New York, Stony Brook. The presentations were made by E. Leonard Jossem, retiring past President of the Association, at its annual business session on 31 January 1975 in Anaheim.

ISSN:0002-9505    

DOI:10.1119/1.9831

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

Remarks by the Chairman of the Committee on Awards in presenting Robert Resnick the award of the 1974 Oersted Medal in recognition of his notable contributions to the teaching of physics.

ISSN:0002-9505    

DOI:10.1119/1.9832

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

Editor’s note: The Editor heard Professor Heisenberg deliver the substance of this article as a lecture at Harvard University. We are grateful that permission has been granted to reprint this presentation from its original source.

ISSN:0002-9505    

DOI:10.1119/1.9833

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

A survey is made of 24 years of this Journal’s seeking evidence of physics courses with national stature, courses with extensive evaluation, and evidence of national, regional, or multi‐institutional study of college physics teaching. During this period there were 85 course or laboratory reports, but the majority (59) occurred in the last four years. Few contained extensive evaluation reports, only two achieved national stature, and the outlook for large‐scale study and evaluation of physics programs looks bleak. There may be cause for optimism, however, in the editorial policy change for the American Journal of Physics discussed in the September 1973 issue. Evidence that a change may already be occurring is offered in this article.

ISSN:0002-9505    

DOI:10.1119/1.9834

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

The authors describe four instructional innovations recently put into effect at the State University of New York at Stony Brook. The first is an inquiry‐oriented physical science course which serves primarily prospective elementary school teachers. The second is a large, self‐paced introductory course taken largely by biological science majors and premeds. In a more ambitious effort, a liberal arts physics major program has been designed. The outstanding features are that the course topics emphasize the historical and social side of physics, the choice and sequencing of courses is flexible, and students learn to use physics in a variety of contexts other than physics research. Finally, undergraduates and graduate physics students at Stony Brook have opportunities to produce instructional materials under supervision as part of their education in physics.

ISSN:0002-9505    

DOI:10.1119/1.9835

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

A common complaint leveled against the Millikan oil drop experiment, as ususally performed in the undergraduate physics laboratory, is that it often yields values of the electronic charge with inexplicably gross errors. Both students and instructors find such in‐the‐ballpark values of e highly unsatisfactory. The chief purpose of this article, as far as the value of the electronic charge is concerned, is to show that acceptable values of e are obtainable when polystyrene spheres of specified uniform diameter and density are substituted for oil drops in the experiment. This substitution eliminates the errors associated with the use of oil drops of unknown and variable size and removes much of the guesswork involved in assigning proper index integers to the observed charges, a likely source of error in the oil drop experiment. Because the size of the spheres is given in advance, we can make two independent determinations of the value of e, one with the use of Stokes’s law and a second without its use. Finally, because of the small size of the spheres, we can also make an estimate of the value of the Boltzmann constant, using the effects of Brownian motion on the dispersions of the sets of time measurements taken in the experiment.

ISSN:0002-9505    

DOI:10.1119/1.9836

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

In electron microscopy of biological materials, the samples must be specially prepared before they can be placed in the high vacuum of an electron microscope. If the samples are prepared in water and if the last stages of the preparation involve evaporation of water from a liquid–vapor interface, surface tension at the interface can generate very high pressures in micrometer‐size structures that will distort the structures to the point where much information about their original shapes and configurations is lost. In order to avoid this damaging distortion, the samples are immersed in a fluid such as liquid CO2in a pressure vessel and the fluid is heated to a temperature higher than its critical temperature where it becomes a gas and can then be removed without the damaging effects of surface tension. The physical details and the advantages and disadvantages of alternative ways of carrying out the process are reviewed. Optimum conditions for carrying out the process are identified, and it is noted that some of the essentials of the process are frequently misunderstood. This ’’practical application’’ of the physics of the critical point can be used to advantage to help students learn about the PVT behavior of real substances and it is of special interest to students in biological sciences.

ISSN:0002-9505    

DOI:10.1119/1.9837

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

A new approach to axiomatizing quantum theory is suggested that overcomes some of the problems of the more usual methods. The measurement process is not left as a primitive under the new approach, and the density operator is taken as describing the fundamental physical properties of a system. Some differences from the Bohr and Margenau–Park approaches are mentioned.

ISSN:0002-9505    

DOI:10.1119/1.9804

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP

摘要:

An electrostatic pendulum oscillator was theoretically analyzed. In this theory, infinitely large electrodes are assumed, so that the electric force can be approximated by a constant for small angles of pendulum motion. The charge acquired by a sphere was calculated by both approximation and numerical method. Then the relationship between applied voltage and frequency was obtained, which might be approximated by a linear relation at higher voltage. The theory was compared with the experimental results of Martin and Longbrake. Even though the electrode configuration is different, the theory agreed reasonably well with the experimental data. Further improvement of the theory is suggested.

ISSN:0002-9505    

DOI:10.1119/1.9805

出版商:American Association of Physics Teachers    

年代:1975

数据来源: AIP