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Half-life

rad6210

New member
Joined
Sep 13, 2009
Messages
21
Suppose a particular kind of atom has a half-life of 1 year. Find:
a) the probability that an atom of this type survives at least 5 years
b) the time at which the expected number of atoms is 10% of the original
c) if there are 1024 atoms present initially, the time at which the expected number of atoms remaining is one
d) the chance that in fact none of the 1024 original atoms remains after the time calculated in c)

Hey ya'll. The idea of half-life has always kind of confused me, so if anyone knows how to just get me started on these .... Thanks!
 

DrMike

Full Member
Joined
Mar 31, 2009
Messages
252
The half life is the time after which the probability of disintegration is 1/2.

If the half-life is T, the probability of lasting t is 0.5^(t/T).
 
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