Question

If the radioactive decay constant of radium is $1.07\times {10}^{-4}$ per year, then its half life period is approximately equal to

• A. $8,900years$
• B. $7,000years$
• C. $2,520years$
• D. $6,476years$

Answer 1

The correct option is D $6,476years$

$\begin{array}{c}\lambda =1.07\times {10}^{-4}\\ {\tau }_{1/2}=\frac{{}^1{n}_2}{1.07\times {10}^{-4}}=\frac{0.693}{1.07\times {10}^{-4}}\\ =0.6476\times {10}^4\\ \approx 6476years\end{array}$

Hence,

Option $D$ is correct answer.