A woord specimen from an archeological centre shows a `._(6)^(14)C` activity of 5.0 counts/min/gm of carbon. What is the age of the specimen (`t_(1//2) " for " ._(6)^(14)C` is 5000 years) and a freshly cut wood gives 15 counts/min/g of carbon

Options

A. `5.78 xx 10^(4)` years
B. `9.85 xx 10^(4)` years
C. `7.85 xx 10^(3)` years
D. `0.85 xx 10^(4)` years

Answer

C

Explanation

`t = (2.303)/(0.693) xx 5000 xx "log" (15)/(5)`
`= (2.303)/(0.693) xx 5000 xx log 3 = 7927 = 7.92 xx 10^(3) yrs`