Radioactivity (5 experiments)

Introduction

We can find many technical, industrial or diagnostic applications, where ionizing devices are used, such as smoke detectors in fire detectors, x-ray devices for industrial or medical diagnosis, sterilization of food and medical instruments. Ionizing radiation can have healing effects (eg. meet with  Leksell gama knife, which is situated at Hospital Na Homolce in Prague), but it can also have devastating effects. That is reason why everyone should know well about elemetary ways how to protect against ionizing radiation and recognize types of radiation.

We distinguish several types of ionizing radiation, which differ by their penetration through materials.

Pic. 1: Shielding wall made of lead. (Picture taken from website of corporation Plehaso, KG)

Basic and intuitive ways of protection against ionizing radiation are:

In the first and second case there is no need of special eqipment. Also we don't need to protect against natural radioactive background. Live forms on earth are well adapted; eg. in cells there are self-repair mechanisms of DNA double helix (which carries genetic informaton), which are effective up to certain damage. On the contrary radioactivity participated on rich biodiversity on earth.

Radioactivity - spontaneous transformation of nuclei of unstable chemical elements, which is accompanied by creation of ionizing radiation, is random physical phenomenon, that is unable to predict. However, it is well described by means of statistical physics. In this experiment you will be learn something about statistics, therefore you will be able to check simple relations, which are used in radioactive shielding.