A radioactive nucleus A with a half life T, decays into a nucleus B. At t=0, there is no nucleus B. At sometime t, the ratio of the number of B to that of A is 0.3. Then, t is given by :
As we learnt in
Number of nuclei after disintegration -
or
- wherein
Number of nucleor activity at a time is exponentional function
Number of nucleus of A at any time t is
NB= Number of nucleus of A that decayed tinto B
Taking log
Correct answer is 2
Option 1)
This is an incorrect option.
Option 2)
This is the correct option.
Option 3)
This is an incorrect option.
Option 4)
This is an incorrect option.
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