[" During mean life of a radioactive element,"],[" the fraction that disintegrates is "]

What is mean life of a radioactive element?

True or False Statements : In a radioactive element the fraction of initial amount remaining after its mean life time is l/e.

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

Half life period and mean life period of a radioactive element are

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

Fill in the blanks with appropriate items : The half-life period of radioactive element _______ minute if 75% of it disintegrates in 40 min.