The isotopes and occur in nature in the ratio 140:1

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

Problem

The isotopes

\text{U}^{238}

and

\text{U}^{235}

occur in nature in the ratio 140:1. Assuming that at the time of earth formation, they were present in equal ratio, make an estimation of the age of earth. The half-life period of

\text{U}^{238}

and

\text{U}^{235}

are

4.5 \times 10^9

and

7.13 \times 10^8

year respectively.

Related theory

Radioactivity
Nuclear physics
Radioactive decay

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