Physics

Problem

The parent nuclide

Q

has a half-life of

4.5\,\text{d}

and begins with an initial sample of

Q_0

. Researchers wish to wait until fewer than

3\%

of the original

Q

remains so that radiation from its daughter products dominates the signal. Approximately how long should they wait? a)

18\,\text{d}

9.0\,\text{d}

27\,\text{d}

22.5\,\text{d}