In a sample of radioactive material, what percentage of the initial number of active nuclei will decay during one mean life ?

In a sample of radioactive material , what fraction of the initial number of active nuclei will remain undisintegrated after half of the half life of the sample ?

In a sample of radioactive material , what fraction of the initial number of active nuclei will remain undisintegrated after half of the half life of the sample ?

In a sample of radioactive material, what fraction of initial number of active nuclei will remain undistintegrated after half of a half0life of the sample?

In a sample of radioactive material, what fraction of initial number of active nuclei will remain undistintegrated after half of a half0life of the sample?

Four thousand active nuclei of a radioactive material are present at t= 0. After 60 minutes 500 active nuclei are left in the sample. The decay constant of the sample is

Four thousand active nuclei of a radioactive material are present at t= 0. After 60 minutes 500 active nuclei are left in the sample. The decay constant of the sample is

The activity of a given sample of radioactive material is reduced to (1/32) of its initial value in 25 days. The half life in days is

Assume that the rate at which radioactive nuclei decay is proportioanl to the number of such nuclei that are present in a given sample. In a certain sample 10% of the original number of radioactive nuclei have undergone disintegration in a period of 100 years. What percentage of the original radioactive nuclei will remain after 1000 years.?

The rate at which radioactive substances decay is known to be proportional to the number of such nuclei that are present in a given sample. In a certain sample 10% of the original number of radioactive nuclei have undergone disintegration in a period of 100 years. Find what percentage of the original radioactive nuclei will remain after 1000 years.