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Smoke detectors

  1. Aug 23, 2004 #1
    I just noticed my new $10 smoke detector contains a few microcuries or less of radioactive Americium. Anyone one knows how these work? Why this element? It's the first time I see an application for it.
  2. jcsd
  3. Aug 23, 2004 #2
    Google search string: smoke detector radiation yields this among the search results

    I don't know why that element; probably it is cost efective and safe.

    Keep on chuggin !!

  4. Aug 23, 2004 #3
    If I remember correctly, Americium is pretty much the lowest decay of radiactivity. It emits quite a bit of alpha waves. There is a sensor that picks up the alpha waves, and thus the smoke detector doesn't ring. When the smoke is there, the waves are scattered, and thus it rings :)

    It was a project I did quite some time ago, so I'm not sure if I'm completely right. Feel free to correct me.
  5. Aug 23, 2004 #4
  6. Aug 24, 2004 #5
    Thank you guys. Fun to see those funky elements are good for something.
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