Physics

Problem

Nuclide

A

decays to nuclide

B

with decay constant

\lambda_A=0.040\,\text{s}^{-1}

. Nuclide

B

decays to a stable product with decay constant

\lambda_B=0.10\,\text{s}^{-1}

. Assuming the sample is initially pure

A

, at what time after the start of the decay chain is the activity of

B

greatest? a)

6.9\,\text{s}

25\,\text{s}

15\,\text{s}

11.6\,\text{s}