Describes a precise yet simple method for computing eigenvalues and eigenvectors of a symmetric matrix useful in teaching quantum mechanics. (SK)

The lack of parallelism between the force and acceleration vectors has several apparently paradoxical consequences that have been recently examined. This article uses a different and more general mode of analysis than previous authors to derive quite general, rather than particular, results. (Author/SK)

Describes a model for inelastic scattering obtained by suitably generalizing scattering from a square well. The generalization introduces matrices into the quantum-mechanical scattering equations, which may be solved exactly to give an explicit expression for the scattering matrix. Discusses the results it predicts for a simple example. (Author/SK)

Compares neutrino and photon emissions, develops the thermodynamic blackbody laws of neutrino emission analogous to laws governing photon emission, points out that combined radiation from a "true blackbody" consists of both photon and neutrino emissions of comparable magnitude, and speculates upon the existence of blackbody neutrino…

Simple and efficient methods for adding angular momenta and for finding angular momentum eigenstates for systems of equivalent electrons are developed. Several different common representations are used in specific examples. The material is suitable for a graduate course in quantum mechanics. (SK)

Since Maxwell's relations are derived in general form from the first to second laws, and students often wonder what they mean and how they are used, appropriate partition functions for van der Waals gas and the nuclear paramagnetic system are used to obtain entropy expressions and equations of state. (Author/SK)

Describes an exercise, suitable for use on programmable calculators or microcomputers, to calculate some of the rapidly processing orbits of a mass M near a static black hole star of mass M. (SK)

A model is introduced for the simulation of Boltzmann-like binary interactions which may be extended to exhibit the effect of angular dependence in the scattering cross section and other dynamical aspects of two-body interactions. (Author/SK)

Simpler than x-ray diffractometer experiments, the experiment described illustrates certain concepts regarding the interaction of electromagnetic rays with matter such as the exponential decrease in the intensity with absorber thickness, variation of the coefficient of absorption with energy, and the effect of the K-absorption edge on the…

Introduces an experiment that can be demonstrated in the classroom to show that shear waves, Rayleigh waves, and Lamb waves can be easily generated and observed by means of mode conversion. (Author/CS)

The general problem of mass accretion by a drop falling through a cloud of droplets is considered as an exercise in introductory or intermediate mechanics. The kinematic behavior of the falling drop is deduced for a variety of mechanisms of mass accretion, and some special limiting conditions are discussed. (Author/SK)

Specific illustrations are given of questions and problems designed to lead students in introductory physics courses into visualizing and reasoning qualitatively about physical phenomena. Examples include phenomena related to mechanics, electrostatic/magnetic interactions, resistive direct-current circuits, and Thompson's experiments marking the…

An air-track and glider system used to demonstrate Newton's second law is described. Advantages of using the system are included. (SK)

Discusses how the adiabatic law for ideal gases can be derived from the assumption of a Maxwell-Boltzmann (or any other) distribution of velocities--in contrast to the usual derivations from thermodynamics alone, and the higher-order effect that leads to one-body viscosity. An elementary derivation of the adiabatic law is given. (Author/DS)

Advanced undergraduate experiments utilizing a commercially available, thin spontaneous fission source are described, including studies of the energy and mass distribution of the fission fragments and their energy and angular correlation. The experiments provide a useful introduction to fission, nuclear mass equations, heavy-ion physics, and…