Two samples X and Y contain equal amounts of radioactive substances. If `1/16 th` of a sample X and `1/256 th` of sample Y remain after 8h, then the ratio of half periods of X and Y is

Two radioactive samples A and B have same number of atoms initially. After 6 hours, I/8th of sample A and l/32th of sample B remains. The number of half-lives of A and B are n_(1) and n_(2) The ratio of half-lives of A and B is

A sample contains two radioactive substances A and B in the ratio of 4 : 1 . If their half lives are 24 and 16 hours respectively , then after two days what will be the ratio of A and B?

The fraction of the radioactive sample will remain undecayed after 4 half-life periods is

Two samples of different radioactive substances initially have the ratio of active nuclei 4 : 1 and then half lives are 12 hr. and 16 hr. respectively. Find the ratio of active nuclei of the two samples after 2 days.

Three samples of a radioactive substance have activity in a ratio 2 : 5 : 7 , then after two half lives the ratio of their activities will be: