RADIATION! There are many sources all round us, such as microwaves, televisions, radios, cell phones and the sun that bombard us with radiation every day. Radiation can be used by archaeolo gists to determine the ages of some fossils and rocks and it is often used by doctors in medical treatments. What is radiation? Is all radiation harmful? What are safe levels of exposure? What factors affect the amount of radiation that we are exposed to?

You will use your CBL-calculator set-up together with the Geiger Counter probe to investigate radiation by measuring and graphing the amounts of radiation emitted by three different sources at several different distances during varying time periods. You will need to set up your CBL by choosing the correct probe and channel and then setting the Trigger Prompt feature to make readings of varying time duration from 10 seconds to 60 seconds. You will also manually position the probe to take readings at distances ranging from 60 cm to 0 cm for equal periods of time.

Write up your lab as you usually do including very specific procedure for setting up the probe and collecting your data. Print out and attach all data tables and graphs, making sure that they are labeled clearly. Keep the following questions in mind as you work and answer them when you have finished.

1. Which factors are being tested?

2. Are the graphs the same for all three sources? If not, how do they differ?

3. Are the graphs the same at all distances? If not, how do they differ?

4. Are the graphs the same for all exposure times? If not, how do they differ?

5. What can you conclude about reducing your exposure to harmful radiation?