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Homework Help: Radioactive decay.

  1. Sep 18, 2005 #1
    Simple question, but i dont know where to start.

    The half life of one radioactive isotope of sodium is 2.6 years. Show that its decay constant is 8.4 x 10^-9 s^-1.

    Thanks in advance,

  2. jcsd
  3. Sep 18, 2005 #2
    [tex] T_h = \frac {ln2} { \lambda} [/tex]

    But remember to convert the time into seconds!
    Last edited: Sep 18, 2005
  4. Sep 18, 2005 #3
    Do you know the following identity [itex]T = \frac{ln 2}{\lambda}[/itex], where [itex]T[/itex] is the half life in seconds and [itex]\lambda[/itex] is the decay constant.
  5. Sep 18, 2005 #4
    Ah got it,

    Thanks guys.

    Was a simple error, i converted it to seconds by doing =

    2.6 x 365 x 3600. And i forgot about the hours.

    3600 x 24 x 365 x 2.6 = no.seconds gave the correct answer.

    Silly mistake.
    Last edited: Sep 18, 2005
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