The half-life for radioactive decay of `14_{C}` is 5730 years. An archaeological artifact containing wood had only 80 % of the `14_{C}`found in a living tree. Estimate the age of the sample.

An archaeological substance contained wood had only 66.66% of C^14 found in a tree. Calculate the age of the sample if the half life of C^14 Is 5730 years.

On analysis a sample of Uranium was found to contain 0.2777 g of ""_(82)Pb^(206) and 1.667 g of ""(92)U^(238) . The half-life periodof ""_(92)^(238) is 4.51 xx 10^(9) years. If all the lead were assumed to have come from decay of ""_(92)^(238) , What is the age of the earth ?

The radio isotope ""_(15)^(32)P is used to bio-chemical studies. A sample containing this isotope has an activity 1000 times the detectable limit. How long could an experiment be run with the sample before the radioactivity could no longer be detected ? Half-life of ""_(15)^(32)P is 14.2 days.

A small amount of solution containing a radioactive nucleide A was administered into blood of a patient. The activity of the nucleide is 2 xx 10^(3) dps. Its half life is 15 hours. After 5 hours a sample of the blood drawn out from the patient. It's activity was 16 dpm per mL. Radioactive nuclide A^(x) decays by beta^(-) emission (42%) beta^(+) emission (58%) in the patient body Then half value of beta^(-) decay path is

What is the mass of ""^(14)C isotope that will have an activity of one curie if half-life period of ""^(14)C is 5730 years ?