We present a MATLAB script INSOLATE.m that calculates insolation at the top of the atmosphere and the total amount of daylight during the year (and other quantities) with respect to geographic latitude and Earth's obliquity (axial tilt). The script output displays insolation values for an entire year on a three-dimensional graph. This tool…

A simple undergraduate experiment designed to study cooling purely by radiation and cooling by a combination of convection and radiation is described. Results indicate that the contribution from radiative cooling in normal laboratory experiments is more significant than students often realize, even in the case of forced cooling. (Contains 1…

A computer model of the decay of a radioactive series, written in Visual Basic in Excel[TM], is presented. The model is based on the random selection of cells in an array. The results compare well with the theoretical equations. The model is a useful tool in teaching this aspect of radioactivity. (Contains 4 figures.)

An interstellar Bussard ramjet is a spaceship using the protons of the interstellar medium in a fusion engine to produce thrust. In recent papers, it was shown that the relativistic equation of motion of an ideal ramjet and that of a ramjet with radiation loss are analytical. When a mass loss appears, the limit speed of the ramjet is more strongly…

A method is described for building a cost effective digital circuit capable of monitoring the solar radiation incident upon a remote solar cell. The circuit is built in two sections, the first, digitises the analogue voltage produced by the solar cell at a remote location and transmits the received signal to the second receiver circuit which…

Background: Skin cancer, the most common cancer in the United States, accounts for over one million cases per year. Risk can be mediated by limiting UV radiation exposure, yet efforts to increase adoption of protective measures have met with limited success. Purpose: This study compares the results of surveys conducted in 1990 and 2007 assessing…

We present a teaching module dealing with the thermal effects of interaction between radiation and matter, the infrared emission of bodies and the greenhouse effect devoted to university level and teacher education. The module stresses the dependence of the optical properties of materials (transparency, absorptivity and emissivity) on radiation…

Many phenomena generate interesting audible time series. This data can be collected and processed using audio software. The free software package "Audacity" is used to demonstrate the process by recording, processing, and extracting click times from an inexpensive radiation detector. The high quality of the data is demonstrated with a simple…

The school day makes up a major part of a child's everyday life. The time children spend outside of the classroom, including recess, lunch, physical education classes, field trips, and after-school activities, can result in a significant amount of sun exposure, especially if it occurs during the hours of peak sun intensity from 10 a.m. to 4 p.m.…

The purpose of this study was to use acoustic analyses to describe speech outcomes over the course of 1 year after radial forearm free flap (RFFF) reconstruction of the tongue. Eighteen Canadian English-speaking females and males with reconstruction for oral cancer had speech samples recorded (pre-operative, and 1 month, 6 months, and 1 year…

The dipole radiation from an oscillating charge is treated using the Hamiltonian approach to electrodynamics where the concept of cavity modes plays a central role. We show that the calculation of the radiation field can be obtained in a closed form within this approach by emphasizing the role of coherence between the cavity modes, which is…

Context-aware ubiquitous learning (u-learning) is an innovative approach that integrates wireless, mobile, and context-awareness technologies to detect the situation of learners in the real world and provide adaptive support or guidance accordingly. In this paper, a context-aware u-learning environment is developed for guiding inexperienced…

Following on from our previous article (Oon and Subramaniam 2009 "Phys. Educ." 44 384-91), here we trace ideas on the history of light from the Planck era to modern times. In particular, the seminal contributions of Planck, Einstein and de Broglie are highlighted. Some lesser known facets of the nature of light are also emphasized. It is stressed…

The possibility of extremely low frequency electromagnetic fields (ELF EMF) causing a number of medical conditions and common symptoms remains a concern and presents somewhat of a quandary to health educators in view of conflicting results. This study investigated the relationship of a number of EMF sources to reported symptoms in an attempt to,…

The article presents a technique to measure the ultraviolet index using a personal hand-held ultraviolet meter to illustrate concepts of physics. Measurements of the erythemally effective (sun-burning) direct solar beam, diffuse skylight, and total global ultraviolet irradiance are converted to daily ultraviolet index measurements. Daily…