CAPE Physics Unit 2 · 2007 (Specimen) · Paper 1 · Question Q44

An archaeologist finds an ancient wooden relic and obtains its count rate as 20\text{ counts per minute per gram} of sample. The count rate obtained from the bark of a living tree is 104\text{ counts per minute per gram} and the background count rate is 8\text{ counts per minute}. What is the approximate age of the relic? [Radioactive carbon ^{14}_{6}\text{C} has a half life of 5600\text{ years}]

1. (A)3000\text{ years}
2. (B)11\ 000\text{ years}
3. (C)17\ 000\text{ years}
4. (D)22\ 000\text{ years}