One -fourth of the amount of a radioactive element decays is 2490 years . Find out the half-life of this element .

One-fourth part of a radioactive element is disintegrated in 664 y. Determine the half-life of the element .

What is half life of radioactive element?

Mean life of a radioactive element is one year. Then its half life is (in year)

Half-life period for radioactive element is

Half-life period for radioactive element is

The rate of decay of a radioactive element at t=0 instant 10^(3) disintegrations per second. If the half life of the elements is Is, then the rate of decay after Is will be