kushak
Jan 9, 2011, 07:57 PM
The activity of a sample of a radioactive isotope is 1800Bq. If this isotope has a half-life of 16 days, what is the activity after 16 days? 24 days? and 60 days?
Unknown008
Jan 10, 2011, 10:57 AM
Since the sample has a half-life of 16 days, it means that after 16 days, it's activity will drop to half its initial activity.
You can put the activity of the sample at any time t, with initial activity Ao, final activity at time t being A and half life h as follows:
\frac{A}{A_o} = \(\frac12\)^{(t/h)}
This gives you the activity A at any time t as:
\frac{A}{1800} = \(\frac12\)^{(t/16)}
Plug in 16, 24 and 60 to get the various activities.
Post what you get! :)