What’s happening when a match is lit? From Answers.com:
Matches contain sulfur, glass powder, and an oxidizing agent as the components in the match head. When you strike a match, the friction due to the particles of glass powder rubbing together generates enough heat to convert some of the red phosphorous to white phosphorous, which burns in the presence of oxygen gas. The heat from the friction also causes the oxidizing agent to produce oxygen gas, igniting the small amount of white phosphorous. Once ignited, the oxygen gas fuels the flame while the rest of the sulfur catches on fire. Of course, this entire process happens in a fraction of a second.
In the year 2020, seven of the largest mirrors on Earth — 20 tons each — will come together in a 22-story, rotating building located in the southern Atacama Desert of Chile. They will form the Giant Magellan Telescope, a feat of science, technology, engineering and math that will have ten times the resolution of the Hubble Space Telescope.
In this video from July 2013, Dr. Wendy Freedman, Chairman GMT, and Dr. Pat McCarthy, Director GMT, explain the astounding challenge of creating this precise, powerful, and wondrous machine. Read more at Phys.org.
Seeing a Styrofoam cup stuck on a fence one day got Park thinking about the chain links properties of being both rigid and porous, of acting as a boundary while retaining an appearance of openness…
Explains Park, “Like a net, the sculpture is a filter that is meant to capture the light that is already there and force it to reveal itself. Now we can see it, the light, in purple shadows and yellow-green reflections that both mirror the shape of the fence and restructure the space they inhabit.”
Related watching from Rice University, a physicist’s perspective on Park’s shimmering, iridescent piece, featuring Jason Hafner, Associate Professor of Physics, Astronomy and Chemistry at Rice, and a time-lapse of the installation:
From a yard in Kampala, Uganda, Moses explains how to build a solar oven using a tire, some glass, newspaper, silver foil, tape, a black pot, and a few hours.
If you’re cooking outside or don’t have an oven, solar ovens are a great alternative for making a hot meal. Building materials are generally inexpensive and easy to find, and rather than requiring fuel or firewood, solar ovens take advantage of a sustainable resource: the sun.How does it work?
Concentrating sunlight: A reflective mirror of polished glass, metal or metallised film concentrates light and heat from the sun on a small cooking area, making the energy more concentrated and increasing its heating power.
Converting light to heat: A black or low reflectivity surface on a food container or the inside of a solar cooker improves the effectiveness of turning light into heat. Light absorption converts the sun’s visible light into heat, substantially improving the effectiveness of the cooker.
Trapping heat: It is important to reduce convection by isolating the air inside the cooker from the air outside the cooker. A plastic bag or tightly sealed glass cover traps the hot air inside. This makes it possible to reach temperatures on cold and windy days similar to those possible on hot days.
Greenhouse effect: Glass transmits visible light but blocks infrared thermal radiation from escaping. This amplifies the heat trapping effect.
For more information about how to make different kinds of solar ovens, visit MAKE or Instructables, or come up with your own solution!