SOLUTION: A radioactive substance that has a half-life of 8 days is to be temporarily implanted in a hospital patient until three-fifths of the amount originally present remains. How long sh
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Question 193628: A radioactive substance that has a half-life of 8 days is to be temporarily implanted in a hospital patient until three-fifths of the amount originally present remains. How long should the implant remain in the patient? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! A radioactive substance that has a half-life of 8 days is to be temporarily
implanted in a hospital patient until three-fifths of the amount originally
present remains. How long should the implant remain in the patient?
:
The half-life equation: Ao*(2^(-t/h)) = A
Where
A = .6; which is
Ao = 1
h = 8 days
t = time in days
:
1*2^(-t/8) = .6
:
2^(-t/8) = .6
: log(2) = log(.6)
find the logs of 2 and .6 = -.222
-.301t = 8 * -.222
-.301t = -1.7748
t =
t = 5.9 days
;
:
Check on a calc: enter 2^(-5.9/8) = .599 ~ .6
