SOLUTION: After the release of radioactive material into the atmosphere from a nuclear power plant in a country in 1981
​,
the hay in that country was contaminated by a radioactive
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​,
the hay in that country was contaminated by a radioactive
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Question 1128536: After the release of radioactive material into the atmosphere from a nuclear power plant in a country in 1981
,
the hay in that country was contaminated by a radioactive isotope (half-life 7
days). If it is safe to feed the hay to cows when 15
%
of the radioactive isotope remains, how long did the farmers need to wait to use this hay? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! After the release of radioactive material into the atmosphere from a nuclear power plant in a country in 1981, the hay in that country was contaminated by a radioactive isotope (half-life 7 days).
If it is safe to feed the hay to cows when 15% of the radioactive isotope remains, how long did the farmers need to wait to use this hay?
:
Using the radio-active decay formula; , where
A = resulting amt after t time
Ao = initial amt
t = time in days
h = half-life in days
:
let A=1, the Ao= .15
: = = -2.737
t = -7 * -2.737
t = +19.158 days, say cow can start eating it in 20 days safely
