A sample of a radionuclide has an initial activity of

PHYSICS · Single correct · A Level · Physics · Nuclear physics · Nuclear physics

Problem

8000\ \text{counts s}^{-1}

. Its half-life is

3\,\text{h}

. What will be the activity after

9\,\text{h}

? (a)

2000\ \text{counts s}^{-1}

(b)

1000\ \text{counts s}^{-1}

(c)

400\ \text{counts s}^{-1}

(d)

1250\ \text{counts s}^{-1}