Question

examine the count rate results from a geiger counter used to measure the radioactivity of a sample for 3 minutes. what is the approximate half - life of the sample? remember - start by finding half of the count rate at 0 1 hour 4 1/2 hours 2 hours 2 1/2 hours 6 hours

Explanation:

Step1: Calculate half of the initial count rate

Half of \(650\) is \(\frac{650}{2}=325\)

Step2: Find the time when the count rate is close to \(325\)

Looking at the table, at \(t = 2\) hours, the count rate is \(373\); at \(t=3\) hours, the count rate is \(283\). Since \(325\) is closer to \(373\) than \(283\), and if we assume a relatively smooth decay (approximate method for half - life from discrete data), we can see that the value \(325\) (half of \(650\)) is closest to the value at \(t = 2\) hours when considering the trend of the data.

Answer:

2 Hours