ENSC 201 Lecture 7: ENSC 201, Lecture 7: Ionizing Radiation
10 Mar 2017
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Document Summary
Extremely low frequency, radio, microwave, infrared, visible light. Static field, power line, am radio, fm radio tv, microwave oven, tv, heat lamp, tanning booth. Alpha particles: heavy, collide with matter and lose their energy quickly, little penetrating power (note: ingestion: limited range but can be damaging. Beta particles: electrons, smaller, penetrate 1-2 cm of water or human flesh. Neutrons: very penetrating, come from splitting atoms in nuclear reactions. Gamma rays: energy transmitted in a wave, great penetrating power. X-rays: similar to gamma except artificially produced. Radioactive gas found naturally in the environment. It is produced by the decay of uranium found in soil, rock, and water. 7. 9% cosmic, 7. 9% terrestrial, 11% internal, 10. 7% medical x-rays, 3. 8% nuclear medicine. Iodine-131: treat thyroid cancer, half life 8 days. Therapeutic radiation: an estimated 5% of secondary cancers are due to radiotherapy. Includes mining, uranium fuel fabrication, waste storage & disposal.
