All forms of radiation are absorbed by matter, but to a varying degree, depending on the density and atomic number of the absorbing material. Gamma radiation is very penetrating and can pass through a considerable thickness of material. The rate at which nuclei in a large assembly decay is dictated by the half-life of the isotope concerned. However, the decay of each individual nucleus occurs completely at random. Set up the equipment according to the diagram.
High voltage needs to be applied to the detector.
Turn on the power to the high voltage supply. The signal from the detector is fed to an amplifier before it can be used by the multichannel scaler board in the computer. Turn on the hand-held Geiger counter and place it near you. Whenever working with radiation you must be careful to be aware of where the sources are located. Sweep the area with the counter so that you become familiar with its function.