A linearization method of the nonlinear differential equation for conservative nonlinear oscillators is analysed and discussed. This scheme is based on the Chebyshev series expansion of the restoring force which allows us to obtain a frequency-amplitude relation which is valid not only for small but also for large amplitudes and, sometimes, for…

Describes: (1) the light beam galvanometer; (2) the electrometer/direct current amplifier; and (3) digital multimeters. Focuses on the uses or potential uses of these instruments in teaching A-level physics. (JN)

Discusses the role of the Francis Bitter National Magnet Laboratory of the Massachusetts of Technology, and its significance in the world of research. Applications of research on magnetism to medicine are emphasized. (SA)

Describes a two-term course in electronic instrumentation for chemistry and physics students. The first term focuses on analog circuits and the measurement of voltage, current, and impendance. The second-term course focuses on digital pulses/logic, microcomputer organization, and assembly language programing and interfacing to experiments. (JN)

Discusses the use of an external analog-digital converter to use a computer as a storage oscilloscope. Provides program listings for use as a unipolar or bipolar voltmeter and storage oscilloscope. Schematics and component list are included. (JM)

Reviews the history of vacuum technology. Includes vacuum pump developments (mechanical, ion, and cyrogenic pumps), measurement techniques, the development of the American Vacuum Society, and electronics in vacuum technology. (JN)

Describes a ripple tank demonstration that displays interference patterns responsible for producing beats and provides photographs of computer simulations of various beat interference patterns. Includes programs for the computer simulation and equations of constructive interference paths in beat interference patterns. (Author/SK)

Describes use of a Fresnel biprism to demonstrate double-slit interference with polarized light. Discusses polarization and phase properties of a randomly polarized gas. (JM)

Four ways in which microcomputers can be turned into laboratory instruments are discussed. These include adding an analog/digital (A/D) converter on a printed circuit board, adding an external A/D converter using the computer's serial port, attaching transducers to the game paddle ports, or connecting an instrument to the computer. (JN)

Describes a low-cost instrument using a solar cell as a sensor to measure both instantaneous and integrated value of solar flux. Constructing and calibrating such an instrument constitutes an undergraduate experimental project, affording students an opportunity to examine a variety of aspects associated with solar energy measurements. (Author/SK)

Microcomputers are commonly interfaced to external devices in scientific, industrial, and consumer settings for data acquisition and for control. The general problem under consideration is the task of taking measurements of some continuous phenomenon, transforming them into digital form, and storing the data in the microcomputer for later use.…

Discusses three types of sensors; pressure, gas detection, and relative humidity. Explains their use for laboratory measurements of gas pressure and detection of specific gaseous species. Shows diagrams of devices and circuits along with examples and applications including microcomputer interfacing. (RT)

Describes an experimental procedure to measure the specific heat of a gas. Discusses equipment, setup, and procedures and provides sample values obtained for air, propane, helium, carbon dioxide, and argon. (JM)

Describes an experiment on a coupled system in which accurate timing is carried out using a Light Activated Switch (LAS) technique. LAS can be used for a wide range of periodic phenomena, provided the amplitude is sufficiently large to interrupt a light beam. (Author/SK)

A description is given of an inexpensive nuclear magnetic resonance (NMR) spectrometer suitable for use in advanced laboratory courses. Applications to the nondestructive analysis of the oil content in corn seeds and in monitoring the crystallization of polymers are presented. (SK)