Radiotion decay

  • Thread starter dagg3r
  • Start date
  • #1
67
0
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
 

Answers and Replies

  • #2
Alexander
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:

Related Threads on Radiotion decay

  • Last Post
Replies
5
Views
2K
  • Last Post
Replies
6
Views
3K
  • Last Post
Replies
11
Views
4K
  • Last Post
Replies
9
Views
3K
  • Last Post
Replies
2
Views
541
  • Last Post
Replies
11
Views
2K
  • Last Post
Replies
2
Views
812
  • Last Post
2
Replies
27
Views
6K
  • Last Post
Replies
6
Views
2K
  • Last Post
Replies
18
Views
5K
Top