A radioactive sample of half-life 30 d contains `10^12` particles at an instant of time. Find the activity of the sample.

A radioactive sample has 2.0 xx 10^(20) active nuclei at a certain instant of time. How many of them will still be in the same active state after three half-lives?

A radioactive sample has half life of 1500 years. A sealed tube containing 1 g of sample will be containing …… of the sample after 3000 years. The missing figure is

A radioactive sample has a half-life of 4 years. Calculate the time in which the activity will be reduced to 25%.

A radioactive sample has a half-life of 20 years. The time at which the activity of the sample will reduce to 10% of its initial value is

At any given time a piece of radioactive material (t_(1//2)=30 days) contains 10^(12) atoms. Calculate the activity of the sample in dps.

A radioactive sample with half-life=T emits alpha -particles. Its total activity is A_(i) at some time and (A_(f)) at a later time. The number of alpha -particle emitted by the sample between these two points in time is

A radioactive sample has 8.0xx10^(18) active nuclei at a certain instant. How many of these nuclei will still be in the active state after two half-life ("in" xx10^(18)) ?

A radioactive sample has 8.0xx10^(18) active nuclei at a certain instant. How many of these nuclei will still be in the active state after two half-life ("in" xx10^(18)) ?