Difference between revisions of "Radioactivity"
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| − | '''Radioactivity''' is the emission of high [[energy]] [[particles]] through the natural phenomenon of the decay of unstable [[isotopes]] of [[chemical elements]] into more stable forms. | + | '''Radioactivity''' is the emission of high [[energy]] [[particles]] through the natural phenomenon of the decay of unstable [[isotopes]] of [[chemical elements]] into more stable forms. |
| − | == | + | The most common types of radiation are called alpha, beta, and gamma radiation.<ref>http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/radact.html</ref> Alpha particles are [[helium]] nuclii; beta particles are high-energy [[electron]]s; gamma rays are high-energy [[photon]]s. Alpha particles can normally be stopped by a sheet of paper, and beta particles can normally be stopped by healthy human skin, but gamma rays can penetrate one's body to cause great harm. |
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| + | ==IAnalogy to disease== | ||
In [[H. G. Wells]]' 1909 novel [[Tono-Bungay]], the narrator muses: | In [[H. G. Wells]]' 1909 novel [[Tono-Bungay]], the narrator muses: | ||
:To my mind radio-activity is a real disease of matter. Moreover, it is a contagious disease. It spreads. You bring those debased and crumbling atoms near others and those too presently catch the trick of swinging themselves out of coherent existence. It is in matter exactly what the decay of our old culture is in society, a loss of traditions and distinctions and assured reactions. ...I am haunted by a grotesque fancy of the ultimate eating away and dry-rotting and dispersal of all our world. So that while man still struggles and dreams his very substance will change and crumble from beneath him. I mention this here as a queer persistent fancy. Suppose, indeed, that is to be the end of our planet; no splendid climax and finale, no towering accumulation of achievements, but just—atomic decay!<ref>Wells, H. G. (1909) [http://www.gutenberg.org/files/718/718-h/718-h.htm Tono-Bungay], online Project Gutenberg text; search for text string "real disease"</ref> | :To my mind radio-activity is a real disease of matter. Moreover, it is a contagious disease. It spreads. You bring those debased and crumbling atoms near others and those too presently catch the trick of swinging themselves out of coherent existence. It is in matter exactly what the decay of our old culture is in society, a loss of traditions and distinctions and assured reactions. ...I am haunted by a grotesque fancy of the ultimate eating away and dry-rotting and dispersal of all our world. So that while man still struggles and dreams his very substance will change and crumble from beneath him. I mention this here as a queer persistent fancy. Suppose, indeed, that is to be the end of our planet; no splendid climax and finale, no towering accumulation of achievements, but just—atomic decay!<ref>Wells, H. G. (1909) [http://www.gutenberg.org/files/718/718-h/718-h.htm Tono-Bungay], online Project Gutenberg text; search for text string "real disease"</ref> | ||
Revision as of 04:24, December 13, 2009
Radioactivity is the emission of high energy particles through the natural phenomenon of the decay of unstable isotopes of chemical elements into more stable forms.
The most common types of radiation are called alpha, beta, and gamma radiation.[1] Alpha particles are helium nuclii; beta particles are high-energy electrons; gamma rays are high-energy photons. Alpha particles can normally be stopped by a sheet of paper, and beta particles can normally be stopped by healthy human skin, but gamma rays can penetrate one's body to cause great harm.
IAnalogy to disease
In H. G. Wells' 1909 novel Tono-Bungay, the narrator muses:
- To my mind radio-activity is a real disease of matter. Moreover, it is a contagious disease. It spreads. You bring those debased and crumbling atoms near others and those too presently catch the trick of swinging themselves out of coherent existence. It is in matter exactly what the decay of our old culture is in society, a loss of traditions and distinctions and assured reactions. ...I am haunted by a grotesque fancy of the ultimate eating away and dry-rotting and dispersal of all our world. So that while man still struggles and dreams his very substance will change and crumble from beneath him. I mention this here as a queer persistent fancy. Suppose, indeed, that is to be the end of our planet; no splendid climax and finale, no towering accumulation of achievements, but just—atomic decay![2]
Notes and references
- ↑ http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/radact.html
- ↑ Wells, H. G. (1909) Tono-Bungay, online Project Gutenberg text; search for text string "real disease"