What fraction of tritium will remain after 25 years? given hlf life of tritium is 12.5 years.

During nuclear explosion, one of the products is overset 90"Sr with half-life of 28.1 years. If 1mug of overset90"Sr was absorbed in the bones of a newly born baby instead of calcium, how much of it will remain after 10 years and 60 years if it is not lost metabolically.

Select the correct statement(s) : a) On bombarding ._(7)^(14)N nuclei with alpha -particle, the nuclei of the product formed after release of proton would be ._(8)^(17)O b) Decay constant does not depend upon temperature c) Nuclide and its decay product after alpha -emission are called isodiaphers d) Half-life of radium is 1580 years . Its average life will be 1097.22 years

After a certain lapse of time,the fraction of radioactive polonium undecayed is foud to be 12.5% of the initial quanitity.What is the duration of this time lapse,if the half life of polonium is 138 days?

Experiments show that radium decomposes at a rate proportioanl to the amount of radium present at the moment. If its half life is 1570 years, what percentage will disappear in one years?

Rohan's age after 7 years is 17 years. What is his age 6 years ago ?

The half-life of ._(6)^(14)C is 5730 year. What fraction of its original C^(14) would left after 22920 year of storage?