摘要:

The conventional estimate of the duration of an atomic collision is the time required to cover an atomic diameter or, if there is a force of attraction, the period of one molecular vibration. Whereas this estimate is adequate for the duration of a head-on collision it fails for eccentric collisions. These are described by “effective potential curves,” which were originally introduced to represent dissociation of diatomic molecules by rotation and take into account the centrifugal force. These curves, different from the ordinary potential curves, show broad maxima outside of the well-known minima. The maxima slow down or even repel the approaching atoms. A pair of atoms whose energy carries it just to the top of a maximum may even perform a part of an unstable rotation. In the general case of eccentric collisions the durations cover a wide range between the period of a molecular vibration and the much longer period of a molecular rotation.

ISSN:0002-9505    

DOI:10.1119/1.1934363

出版商:American Association of Physics Teachers    

年代:1957

数据来源: AIP

摘要:

An analysis is made of the process of emptying a full, open manometer by increasing the pressure at the closed side until the liquid is contained only in the open side, filling the tube; a slight increase in pressure will then result in an explosive eruption of the liquid.

ISSN:0002-9505    

DOI:10.1119/1.1934364

出版商:American Association of Physics Teachers    

年代:1957

数据来源: AIP

摘要:

The aim of the following work is to clarify the definitions of the order of phase transformations, in the case of systems composed of only one substance. First- and second-order phase transformations are discussed with the help of geometrical arguments applied to the intersection of free energy functions. This method also enables us to analyze the behavior of quantities such as the specific heat. As an application, second-order phase transformations of ferroelectric substances are discussed in some detail.

ISSN:0002-9505    

DOI:10.1119/1.1934365

出版商:American Association of Physics Teachers    

年代:1957

数据来源: AIP

摘要:

A discussion of the appropriate place of science, and especially of physics, in engineering education and in general education; and of a university education in our present technological society.

ISSN:0002-9505    

DOI:10.1119/1.1934366

出版商:American Association of Physics Teachers    

年代:1957

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1934367

出版商:American Association of Physics Teachers    

年代:1957

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1934369

出版商:American Association of Physics Teachers    

年代:1957

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1934370

出版商:American Association of Physics Teachers    

年代:1957

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1934372

出版商:American Association of Physics Teachers    

年代:1957

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1934373

出版商:American Association of Physics Teachers    

年代:1957

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1934374

出版商:American Association of Physics Teachers    

年代:1957

数据来源: AIP