A radioactive isotope, used in the agricultural industry has a half life of 8 days. On application, the radiation is emitted is measured at 12500 counts per sec (cps). If the area that it is applied to cannot be used until the radiation strength is less than 50 cps how long will it take before the site can be used again? (Hint assume initial strength is 100%)
(12500)*1/2^n=500
solve for n
n=ln(12500)/ln(500)
n* the number of days (8) =should give you the time it takes to before the site can be used again.
Thank you for your answer. Why is it 500? Sorry I am just trying to understand
Opps, should say
n=ln([12500/500)]/ln(2)
n* the number of days (8) =should give you the time it takes to before the site can be used again.
And you are right it should say 50 not 500.
Typos