The radioactivity of a given sample of whisky due to tritium (half life `12.3` years) was found to be only `3 %` of that measured in a recently purchased bottle marked `''7` years old''. The sample must have been prepared about.

The radioactivity of given sample of whisky due to tritium (Half life=12 yrs) was found to be only 3.125% of that measured in a recently purchased bottle marked "10 years old". By how many years ago the sample must have been prepared?

Natural water contains a small amount of tritium ( _1^3H) . This isotope beta -decays with a half-life of 12.5 years.A mountaineer while climbing towards a difficult peak finds debris of some earlier unsuccessful attempt.Among other things he finds a sealed bottle of whisky.On returm he analyses the whisky and finds that it contains only 1.5 per cent of hte _1^3H radioactivity as compared to a recently purchased bottle marked '8 years old' .Estimate the time of that unsuccessful attempt.

Natural water contains a small amount of tritium (H_1^3) . This isotope beta -decays with a half-life of 12.5 years.A mountaineer while climbing towards a difficult peak finds debris of some earlier unsuccessful attempt.Among other things he finds a sealed bottle of whisky.On returm he analyses the whisky and finds that it contains only 1.5 per cent of hte H_1^3 radioactivity as compared to a recently purchased bottle marked '8 years old' .Estimate the time of that unsuccessful attempt.

Tritium has half life of 12.5 years undergoing beta decay. What fraction of sample of tritium will remain undecayed after 50 years?