Natural uranium is a mixture of three isotopes, ,

PHYSICS · Subjective · A Level · Physics · Nuclear physics · Nuclear physics

Problem

Natural uranium is a mixture of three isotopes,

^{234}_{92}\mathrm{U}

^{235}_{92}\mathrm{U}

, and

^{238}_{92}\mathrm{U}

, with mass percentages

0.01\%

0.71\%

, and

99.28\%

, respectively. Their half-lives are

2.5\times10^5\ \mathrm{yr}

7.1\times10^8\ \mathrm{yr}

, and

4.5\times10^9\ \mathrm{yr}

, respectively. Determine the share of radioactivity of each isotope in the total activity of natural uranium.