At the end of 14 min, 1/16 of a sample of radioactive polonium remains. The corresponding half-life is:
A) (7/8) min
B) (8/7) min
C) (7/4) min
D) (7/2) min
E) (14/3) min

Question

Quizplus · Accepted Answer

The half-life of a substance is the time it takes for half of it to decay. If 1/16 of the sample remains after 14 minutes, it means the sample has gone through 4 half-lives (since 2^4 = 16). Therefore, the half-life is 14 minutes divided by 4, which equals 3.5 minutes or (7/2) minutes.

At the End of 14 Min, 1/16 of a Sample