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Radiation dosages
Radiaton dosages from different sources. Graph by http://xkcd.com/radiation/. xkcd has published an excellent graph showing where different dosages of radiation come from and how they affect health....
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Global Temperature Model: An Application of Conservation of Energy
Energy cannot be either created or destroyed, just changed from one form to another. That is one of the fundamental insights into the way the universe works. In physics it’s referred to as the Law of...
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A Fatal Dose of Bananas
Banana: 1 μS. In my last physics exam, I asked how many bananas would it take to deliver a fatal dose of radiation. This question came up when we were discussing different types of radiation and...
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Living next to Chernobyl
Hanna Zavorotnya, 78, lives in Chernobyl’s dead zone. Image from RENA EFFENDI/ INSITUTE via The Telegraph. We were talking about environmental disasters, specifically nuclear radiation, and looking at...
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Albedo and Absorption
Ice melts around an embedded leaf, taking the pattern of the leaf. Darker colored objects absorb more light than lighter colored objects. Darker objects reflect less light; they have a lower albedo. So...
View ArticleWhat Happens When Two Black Holes Collide?
A student asked this question about black holes during a discussion, and I didn’t have a good answer. Now there’s this: A study last year found unusually high levels of the isotope carbon-14 in ancient...
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