Speed Problems Worksheet #1 - Mrs Morgan's Science Page

0.2. 1 mrad = 62,400 MeV per gram. Rule of thumb: 100 beta particles per cm per second = 10 mrad/hr exposure to the dermal layer of skin with high energy betas. Problem calculate the exposure if a thin window gm tube detector gives 30,000 counts per minute the counter has 5 cm2 surface area and 100% counting efficiency. ................
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