Presents physics problems relating human body weight, activity, and energy expenditure. (SL)

Describes an experiment used to study dielectric properties of materials. Values of the dielectric loss tangent can be determined at low frequencies from Lissajous figures formed on an oscilloscope. Some mineral rock specimens show Debye-type relaxation peaks at frequencies in the region of 1 to 500 Hz. (Author/DS)

Describes the details of constructing, and use of, a solar collector. Uses a black liquid to absorb the energy, the thermosyphon effect to drive the liquid through the collector, and a floodlamp as a surrogate sun. (GA)

Describes an undergraduate experiment which measures the energy gap in silicon and germanium. Theory, procedure, and results of this experiment are included. (HM)

Discusses the calibration of bolometric and photoelectric devices utilized for the measurement of solar energy. (SL)

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…

Provides a derivation of the evolution of an initially black-body spectrum in the closed Friedmann universe. (Author/SL)

Experiments to measure range, range straggling, stopping power, and energy straggling of alpha particles are discussed in this article. Commercially available equipment with simple modifications is used for these measurements. (Author/GA)

Presents basic theory of silicon solar cells and discusses their use in experiments in undergraduate teaching laboratories. (SL)

It is shown that exact pseudopotentials for excited states of hydrogen atoms can be derived. A very simple, novel application of pseudopotential method which displays vividly some of its limitations is presented. (Author/GA)

Describes a method for using ferrofluids to study steady-state resonant vibrations at liquid-air interfaces. (SL)

Electronic energy levels in noble gas atoms may be determined with a simple teaching apparatus incorporating a resonance potentials tube in which the electron beam intensity is held constant. The resulting spectra are little inferior to those obtained by more elaborate electron-impact methods and complement optical emission spectra. (Author/SK)

Corrected are several misconceptions concerning the apparently "missing" energy that results when acoustic or electromagnetic waves cancel by destructive interference and the wave impedance reflected to the sources of the wave energy changes so that the input power is reduced. (Author/CS)

Describes an experimental verification of Stefan's law using commercial electric lamps. (SL)