Question

In one average-life,

• A. half the active nuclei decay.
• B. less than half the active nuclei decay.
• C. more than half the active nuclei decay.
• D. all the nuclei decay.

Answer 1

The correct option is C more than half the active nuclei decay.

Average life of radioactive sample is the amount of time required for it to get decayed by $63.2$% of its original amount. So it is more than half the nuclei decay.