1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Radiotion decay

  1. May 2, 2003 #1
    Radioactive materials are considered to be relatively safe when their activity has fallen below 0.1% of their initial value.
    a How many half-lives does this take?

    a 0.1% = 0.001, and 1/2^n = 1/1000
    n = 10 or 10 half-lives

    how did they get n=10
     
  2. jcsd
  3. May 2, 2003 #2
    2-x = 0.001, so taking logarithm of both sides you get x = -log2(0.001) = 3log2(10)=3/log10(2)=3/0.301 = 9.97 = 10
     
    Last edited by a moderator: May 2, 2003
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Radiotion decay
  1. Orbital Decay (Replies: 6)

  2. Radioactive decay (Replies: 1)

  3. Exponential decay (Replies: 18)

  4. Decay constant (Replies: 9)

Loading...