Describes developments in the field of ultrafast laser clock technology. (SL)

Presents a discussion of the theory of thermoelectric effects and contact potentials. (SL)

Describes the use of free-electron lasers as a source of coherent radiation over a broad range of wavelengths from the far-infrared to the far-ultraviolet regions of the spectrum. Discusses some applications of these lasers, including medicine and strategic defense. (TW)

Presents questions and answers to the 1985 British Physics Olympiad (BPhO) Competition. Comments about the competition (the second year of British participation) and the winners who went to Yugoslavia (and placed second behind the USSR) are included. (JN)

Contains the abstracts and detailed schedule of the American Association of Physics Teachers summer meeting which was held in Columbus, Ohio, June 23-27, 1986. An author index is included. (ML)

Presents report summaries of the regional convocations of the Physics Teaching Resource Agent Group. Includes notes from the Northeast, North Central, Mid-Atlantic, Northwest, South Central, Southeast, and Western regions. Provides an overview of common problems and concerns and highlights successes and suggestions. (ML)

Discusses refraction in terms of the deviation of light. Points out that in physics courses where very little mathematics is used, it might be more suitable to describe refraction entirely in terms of the deviation, rather than by introducing Snell's law. (DH)

Proposes doing away with dimensions and replacing them with base units, extending the checking of feasibility of equations and deriving relationships to base units. (JM)

A retroreflector is a mirror that removes distortion from a light beam. Describes experiments using the retroreflector as well as related phenomena. (JN)

Presents a two-day experiment to estimate the pK for the protolysis of beta-naphtol in its ground state and the first singlet excited state. Results are compared to results obtained from the integrated rate equations in which values of the rate constants were taken from a time-resolved study. (JN)

Several changes in assessment of students in Great Britain are being considered, including establishing a common system of examining at 16-plus and moving toward specifying criteria for the award of grades. Issues related to these trends (including the demise of the General Certificate of Secondary Education--GCSE) are examined. (JN)

Helioseismology (similar to geophysicists' study of seismic waves) makes it possible to penetrate the sun's opaque brilliance by measuring surface oscillations. Their pattern and period hold clues to temperature, structure, composition, and dynamics of the sun's interior. Scientists have used data to build models (evolved mathematically) to…

An annotated bibliography of astronomy books is presented. These books (most of which are designed for research astronomers and graduate students) demand substantial background in astronomy and physics. Nontechnical books are reviewed in part I (SE 537 910). (JN)

A relatively simple opto-electronic setup is described that utilizes a cadmium sulphide (CdS) photoconductive cell to detect resonance of a stretched vibrating string or wire. The display may be either an oscilloscope or a frequency counter. Also describes an inexpensive socket for flanged-base light bulbs. (JN)

A high-impedance comparator suitable for monitoring the resistivity of a deionized or distilled water line supplying water in the 50 Kohm/cm-2 Mohm/cm range is described. Includes information on required circuits (with diagrams), sensor probe assembly, and calibration techniques. (JN)