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Homework Help: Radiation HW on Alpha Particles

  1. Sep 12, 2010 #1
    1. The problem statement, all variables and given/known data

    How much energy does an alpha particle need to penetrate the minimal protective epidermal layer of skin (Thickness ~7 mg cm-2

    2. Relevant equations

    Possibly R=0.56E, E,4
    OR R=1.24E-2.62, 4<E<8

    3. The attempt at a solution

    I used the equation R=0.56E
    so, I said that:

    7 mg/cm^2=0.56E
    then divided by 0.56 to get E=12.mEV

    I guess I'm jsut not sure if I used to correct equation and am confused if the units match up.

    Thanks for your help!
  2. jcsd
  3. Sep 12, 2010 #2
    I think it may be correct if I use to other formula actually. 7 mg/cm^2=1.24E-2.62
    Do the math and it equals 7.8 mEv. Sound like a better answer?
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