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Homework Help: Nuclear Physics

  1. May 23, 2006 #1
    QUESTION

    in an accident in a lab a radioactive isotope with a half life of 3 days is spilled - as a result the radiation is 8 times the max. permissible amount, how long must workers wait before they can enter the room.

    ANSWER

    9

    COMMENTS

    I am not sure where to even start with this one. Please help!
     
  2. jcsd
  3. May 23, 2006 #2

    Pengwuino

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    Gold Member

    Do you know what half life means?
     
  4. May 23, 2006 #3
    half life is the amount of time it takes for the quantity to reduce to half it's initial value.. in this question it takes 3 days for us to get half of the material
     
  5. May 23, 2006 #4

    Pengwuino

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    Gold Member

    So this should be fairly straight forward. If you have 8x the amount and it takes 3 days for half to decay away, how long should it take
     
  6. May 23, 2006 #5
    huh?

    maybe i am missing something here.. but that wouldn't give me 9 as a solution... sorry, I appreciate your help, but am lost on this one.... please help
     
  7. May 24, 2006 #6
    If the radiation is 8x the maximum, 3 days later (which is 1 half life) the radiation would be 4x maximum. Can ou go from there?
     
  8. May 25, 2006 #7
    Thanks. Got it now!
     
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