00029505 Guest Comment: Physics research in undergraduate institutions John Van Zytveld 907 Verification of fundamental principles of mechanics in the computerized student laboratory Shulamith G. Eckstein 909 Slinky-whistler dispersion relation from ‘‘scaling’’ Frank S. Crawford 916 Simple derivation of Lagrange’s three-body equilibrium Daniel F. Styer 917 Measuring small vibrations with interferometry Joshua B. Diamond Denis P. Donnelly James D. Breault 919 Spring–mass chains: Theoretical and experimental studies Mônica Silva Santos Eduardo Soares Rodrigues Paulo Murilo Castro de Oliveira 923 Interference between spontaneous emission in different directions Ming Lai J.-C. Diels 928 Geometric interpretation of a nonlinear gauge Martin Andreas Schweizer 930 The oscilloscope as a measuring instrument B. A. Cooke T. J. Harris H. S. Derbyshire 933 An inductorless double scroll chaotic circuit Thomas P. Weldon 936 Aberration and Doppler shift: The cosmic background radiation and its rest frame T. Greber H. Blatter 942 Perturbation of Uranus by Neptune: A modern perspective H. M. Lai C. C. Lam K. Young 946 The diffraction grating under nonuniform illumination Kenneth S. Mendelson Frank G. Karioris 954 Newton’s law of cooling—A critical assessment Colm T. O’Sullivan 956 Quantum mechanical study of particles in ‘‘softened’’ potential boxes and wells Lewis S. Salter 961 Cyclotron resonance effects in a fluorescent lamp plasma Julie Orr Richard Wolfson 968 Macroscopic motion of a totally isolated system in statistical equilibrium Bernard Diu Claudine Guthmann Danielle Lederer 974 Torque and force on a magnetic dipole Lev Vaidman 978 The exactly solvable Thomas–Fermi atom in two dimensions R. K. Bhaduri S. Das Gupta S. J. Lee 983 Fractal dimension: Limit capacity or Hausdorff dimension? Christopher Essex M. A. H. Nerenberg 986 Tangent law of refraction for heat conduction through an interface and underlying variational principle A. Tan L. R. Holland 988 A tricritical point in the dimerized Ising chain phase diagram C. E. Zaspel 992 Optical bistability experimentation with liquid dyes H. Y. Zhang X. H. He S. H. Tang 994 On the skin effect approximation Glenn S. Smith 996 Expansion coefficients of a squeezed coherent state in the number state basis J. J. Gong P. K. Aravind 1003 The role of kinematics in Hamiltonian dynamics: Momentum as a Lagrange multiplier M. C. Whatley 1006 Why l(l+1) instead of l 2? P. W. Milonni 1012 Perturbation expansion in quantum mechanics B. S. Lee 1012 Tracking the wild eclipse R. J. Manning L. S. Cain 1014 A square-well potential model to describe lambda-hypernuclei P. B. Siegel Mark Farrow-Reid 1016 The Mandelbrot set for binary numbers Peter Senn 1018 Determining e/m with a Bainbridge tube: Less data, more physics William J. Thompson 1019 TIT Guest Comment: Physics research in undergraduate institutions