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

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