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Question
In one average-life,
Options
half the active nuclei decay
less than half the active nuclei decay
more than half the active nuclei decay
all the nuclei decay.
Solution
more than half the active nuclei decay
The average life is the mean life time for a nuclei to decay.
It is given as `tau = 1/lambda = T_"1/2"/0.693`
Here, `tau , lambda and T_"1/2"`
are the average life, decay constant and half life-time of the active nuclei, respectively. The value of the average lifetime comes to be more than the average lifetime. Therefore, in one average life, more than half the active nuclei decay.
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