NEET | 2013Nuclear Physics and RadioactivityHard
Question
The half life of a radioactive isotope ′X′ is 20 years. It decays to another element ′Y′ which is stable. The two elements ′X′ and ′Y′ were found to be in the ratio 1 : 7 in a sample of a given rock. The age of the rock is estimated to be:
Options
A.100 years
B.40 years
C.60 years
D.80 years
Solution
X → Y (stable)
NX Ny

By using
, we have
years = 60 years.Create a free account to view solution
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