摘要:

The appearances of jerk, the third time derivative of displacement, in several papers of mathematical and physical content are reviewed. Two simple nonlinear jerk functions, all of whose solutions are periodic, are introduced and solved. The first has period dependent on initial acceleration but independent of amplitude, and is related to the second-order cubic oscillator. The second, with intrinsically third-order dynamics, has period dependent also on initial displacement. A possible bearing on chaotic jerk functions is mooted.

ISSN:0002-9505    

DOI:10.1119/1.18980

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

This article describes an investigation of student understanding of geometrical optics and illustrates the use of research as a basis for the development of curriculum. Evidence is presented that university students who have studied physics at the introductory level and beyond often cannot apply basic concepts from geometrical optics to account for the pattern produced on a screen when an aperture or obstacle is placed between a light source and the screen. Identification and analysis of student difficulties guided the initial design of a tutorial to supplement instruction in a typical calculus-based or algebra-based course. Development of a laboratory-based, inquiry-oriented curriculum for precollege teachers took place concurrently. Ongoing assessment was an integral part of the curriculum development process. The instructional materials that evolved from this iterative cycle have proved to be effective with the target populations.

ISSN:0002-9505    

DOI:10.1119/1.18988

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

The authors revised the junior-level classical mechanics course at Cornell University to incorporate asynchronous, autonomous, and group learning. We created an E-mail tutorial and a student seminar. We will first discuss the theoretical background for these changes and then describe the results of their implementation over a period of three years.

ISSN:0002-9505    

DOI:10.1119/1.18981

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

In a recent article under the above title (but without the question mark) Henry Stapp has presented arguments which lead him to conclude that under suitable conditions “the truth of a statement that refers only to phenomena confined to an earlier time” must “depend on which measurement an experimenter freely chooses to perform at a later time.” I suggest that this conclusion contains an essential ambiguity as regards the meaning of the expression “statement referring only to phenomena confined to an earlier time,” when such a statement talks about the outcome of an experiment that was not actually performed. As a result Stapp’s argumentation does not imply that future choices can affect present facts. But it does provide a wonderful and instructively different opportunity to reexamine a central point of Bohr’s famous reply to Einstein, Podolsky, and Rosen.

ISSN:0002-9505    

DOI:10.1119/1.18990

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

摘要:

David Mermin suggests that my recent proof pertaining to quantum nonlocality is undermined by an essential ambiguity pertaining to the meaning of counterfactual statements in quantum physics. The ambiguity he cites arises from his imposition of a certain criterion for the meaningfulness of such counterfactual statements. That criterion conflates the meaning of a counterfactual statement with the details of a proof of its validity in such a way as to make the meaning of such a statement dependent upon the context in which it occurs. That dependence violates the normal demand in logic that the meaning of a statement be defined by the words in the statement itself, not by the context in which the statement occurs. My proof conforms to that normal requirement. I describe the context-independent meaning within my proof of the counterfactual statements in question.

ISSN:0002-9505    

DOI:10.1119/1.18989

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.19043

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.18982

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.18994

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.18993

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.18983

出版商:American Association of Physics Teachers    

年代:1998

数据来源: AIP