Question

Wooden article and freshly cut tree show activity of 7.6 and 15.2 $mi{n}^{-1}g{m}^{-1}$ of carbon ( $t_{1/2}=$ 5760 years ) respectively. The age of article in years is:

• A. 5760
• B. $5760\times \left(\frac{15.2}{7.6}\right)$
• C. $5760\times \left(\frac{7.6}{15.2}\right)$
• D. $5760\times (15.2\times 7.6)$

Answer 1

The correct option is A 5760

The activity decreases from 15.2 $mi{n}^{-1}g{m}^{-1}$ to 7.6 $mi{n}^{-1}g{m}^{-1}$.
Thus, the activity is reduced to half.
Hence, the age of the article is equal to the half life period of carbon. It is 5760 years.