A) 6 hours
B) 12 hours
C) 24 hours
D) 128 hours
Correct Answer: B
Solution :
\[\frac{A}{{{A}_{0}}}=\frac{N}{{{N}_{0}}}\] Let safe-level activity be A. Initial activity = 64 A. Hence, \[\frac{N}{{{N}_{0}}}=\frac{A}{{{A}_{0}}}=\frac{A}{64A}\,\,=\,\,\frac{1}{64}\] \[{{\left( \frac{1}{2} \right)}^{n}}\,=\,\frac{1}{64}\,\,or\,\,n=6\] Hence, \[\frac{t}{T}=n=6\] But \[T\,\,=\,\,2\] hours,You need to login to perform this action.
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