If a radioactive substance reduces to `(1)/(16)` of its original mass in `40` days, what is its half-life ?A. 10 daysB. 20 daysC. 40 daysD. None of these

If a radioactive substance reduces to `(1)/(16)` of its original mass

1.	If a radioactive substance reduces to `(1)/(16)` of its original mass in `40` days, what is its half-life ?A. 10 daysB. 20 daysC. 40 daysD. None of these
Answer» Correct Answer - A (a) `(N)/(N_0) = ((1)/(2))^n rArr (1)/(16) = ((1)/(2))^4 = ((1)/(2))^n rArr n = 4` Also `n = (t)/(T_(1//2)) rArr T_(1//2) = (40)/(4) = 10 days`.

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If a radioactive substance reduces to `(1)/(16)` of its original mass in `40` days, what is its half-life ?A. 10 daysB. 20 daysC. 40 daysD. None of these

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