As an alternative to the traditional metallocene laboratory targets, students synthesize Cp[subscript 2]TiCl[subscript 2], bis([eta][superscript 5]-cyclopentadienyl)dichloridotitanium(IV), from the mildly moisture-sensitive cis-TiCl[subscript 4](thf)[subscript 2]. Air-free handling techniques are emphasized, but the (mostly) air-stable,…

A method has been developed to measure the swing period of a simple pendulum automatically. The pendulum position is converted into a signal frequency by employing a simple electronic circuit that detects the intensity of infrared light reflected by the pendulum. The signal produced by the electronic circuit is sent to the microphone port and…

Computer-assisted experiments with CdS and CdSe photoresistors are described. The most important characteristics of the photoresistors are determined: (i) the spectral response, (ii) the photocurrent versus incident radiant power, (iii) the rise and decay time constants and (iv) the frequency response to modulated light. The photoconductivity gain…

A new procedure for performing quantitative measurements in teaching optics is presented. Application of the procedure to accurately measure the rate of change of the variable refractive index of a water-denatured alcohol mixture is described. The procedure can also be usefully exploited for measuring the constant refractive index of distilled…

The "quantum efficiency" (QE) is an important property of a light detector. This quantity can be determined in the undergraduate physics laboratory. The experimentally determined QE of a silicon photodiode appeared to be in reasonable agreement with expected values. The experiment confirms the quantum properties of light and seems to be a useful…

Presents a general overview of various light-related findings with implications for the computer assisted learning environment. Suggests that software developed for instructional purposes incorporate color to maximize visual sensitivity and retention of information while minimizing visual fatigue. (Author/JN)

Chi (2005) proposed that students experience difficulty in learning about physics concepts such as light, heat, or electric current because they attribute to these concepts an inappropriate ontological status of material substances rather than the more veridical status of emergent processes. Conceptual change could thus be facilitated by training…

Described is the use of Thematic Mapper images in undergraduate geology instruction. The work of the Andes Project at Cornell University is discussed. Digitally enhanced illustrations of landforms in the Andes mountains of South America are provided. (CW)

Discusses various types of transducers and explains the use of a photoresistor in sensing light. Describes various hardware and software combinations which can be used with photoresistors in science laboratory experiments. Presents general applications of this instrument in light-meter, solarimeter, and colorimeter experiments. (TW)