This item is a tutorial for introductory physics students on the topic of refraction. It contains an introduction to basic concepts, a brief history of refraction experimentation, refractive index values, light dispersion, and applications of Snell’s equation. Also included are links to six interactive Java simulations related to the refraction of light. This item is part of a larger collection of materials on optics and microscopy developed by the National High Magnetic Field Laboratory and Florida State University.
At this site students will learn that in addition to making elements, supernovae scatter them. They learn that the elements that are made both inside the star as well as the ones created in the intense heat of the supernova explosion are spread out into the interstellar medium. These are the elements that make up stars, planets and everything on Earth including ourselves. Except for hydrogen and some helium created in the Big Bang, all of the stuff we, and the Earth around us, are made of, was generated in stars, through sustained fusion or in supernova explosions.
This U.S. Geological Survey site lists and discusses the properties of volcanic ash. The site contains many helpful diagrams, and explains topics including the size of ash particles, the dispersal of ash by wind, and the kind of eruption that produces ash.
This peer reviewed article from Bioscience magazine is about figs and the diversity of tropical rainforests. Ficus (Moraceae) is arguably one of the most important plant genera in lowland tropical rainforests. A brief review of tropical florulas also demonstrates that Ficus is the only ubiquitously diverse genus in lowland rainforests.
This chapter continues the examination and clarification of concepts relating to point objects, for which as argued in Chapter 1, appropriate, complex/ second order, concepts relate to words like ‘distribution’, ‘dispersion’, ‘density’, ‘pattern’ and ‘scale’ and, at higher level still, third order concepts relating to point process models, stationarity and isotropy/anisotropy.