A sample contains `10^(-2)kg` each of two substances A and B with half lives 4 sec and 8 sec respectively. Their atomic weights are in the ratio `1:2`. Find the amounts of A and B after an interval of 16 seconds.

A radioactive sample contains 10^(-3) kg each of two nuclear species A and B with half-life 4 days and 8 days respectively . The ratio of the amounts of A and B after a period of 16 days is

The number of nuclei of two radioactive substance is the same and their half-lives are 1 year and 2 years respectively. The ratio of their activities after 6 years will be

Two radioactive nuclides A and B have half life of t and 2t respectively . If we start an experiment with one mole of each of them, what will be the mole ratio after a time interval of 6 t ?

Two radioactive nuclides A and B have half-lives in the ratio 2:3 respectively. An experiment is made with one mole of each of them. Calculate the molar ratio of A and B after a time interval of three times of half-line of A .

The radioactive sources A and B of half lives of 2 hr and 4 hr respectively, initially contain the same number of radioactive atoms. At the end of 2 hours, their rates of disintegration are in the ratio :

Two radioactive elements A and B are present in a mixture. Both are beta active. Half lives of A and B are 30 minute and 60 minute respectively. The initial activity of the sample hour only 30 beta particles were detected in an interval of 2 second. Assume that law of radioactivity decay is obeyed. (a) Find the ratio of number of active of A to that of B in the mixture initially. (b) The molar mass of both A and B is closed to 200g. The mixture contains other substance (non radioactive) aprt from A and B. what fraction of the entire mixure is radioactive (fraction by weight) if it is given what mass of the mixture is 1mug .

Two radioactive substances X and Y initially contain an equal number of atoms. Their half-lives are 1 hour and 2 hours respectively. Then the ratio of their rates of disintergration after two hours is

Two radioactive substances A and B have half lives of T and 2T respectively. Samples of a and b contain equal number of nuclei initially. After a time 4T , the ratio of the number of undecayed nuclei of A to the number if undecayed nuclei of A to the number of undeacyed nuclei of B is