Lesson Two: Using a Geiger Counter

Using a Geiger Counter How radioactive are different materials? Materials Geiger counter Radioactive sources such as: cloisonne jewelry commercially available source from a science supply house luminescent clock face Shielding materials such as: paper aluminum foil brick jar of water piece of wood glass pane sheet of lead Directions: 1.One at a time, test each item that is a source of radioactivity by placing the source 2 inches from the Geiger counter probe. Which item has the highest reading?___________ The lowest?__________________________ 2.Place the radioactive source that had the highest reading 2 inches from the Geiger counter probe. One at a time, test each of your shielding materials by placing them between the source and the counter. Do you think the density of the shield is important?______________________________ Why?_________________________________________