The half-life of cobalt-60 is 5.3 years,while that of strontium-90 is 28 years.Suppose you have a sample of each,such that they initially contain equal numbers of atoms of these nuclides.How will the activities (number of decays per second)of the samples compare?
A) The activity of the cobalt-60 sample will be greater.
B) The activities cannot be compared without more information.
C) The activities will be equal.
D) The activity of the strontium-90 sample will be greater.

Question

Quizplus · Accepted Answer

The activity of a radioactive sample is inversely proportional to its half-life. Since cobalt-60 has a shorter half-life (5.3 years) compared to strontium-90 (28 years), the cobalt-60 sample will have a higher activity, meaning it will undergo more decays per second.

The Half-Life of Cobalt-60 Is 5