The rate of disintegration of a radioactivity element changes from initial value of 10,000 dpm to 2,500 dpm in 50 days . The decay constant is

The rate of disintegration of a radioactive substance falls from 800 decay//min to 100 decay//min in 6 hourse. The half life of the radioactive substance is :

The rate of disintegration of a radioactive element at any instant is 10^3 dps. If the half-life of that element is 1 second, then what is its rate of disintegration after 1 second and after 3 second?

The rate of disintegration of a certain radioactive sample at any instant is 8100 dpm. Fifty minutes later the rate becomes 2700 dpm. The half of the radioactive sample will be (Take log2=0.3, log3=0.5, log5=0.7 )

The activity of a radioactive elements (decay constant lambda ) becomes (1)/(3) of initial activity A_(0) in 9 years then the decay constant after 9 years will :

A radioactive substance decay to 1/5 of its original value in 56 days. The decay constant is

The fraction of atoms of radioactive element that decays in 6 days is 7/8. the fraction that decays in 10 days will be

A radioactive substance decays to ( 1/10)^th of its original value in 56 days. Calculate its decay constant.