Radiation
Across
- 3. The time it takes a radioactive material to decay to half the original amount.
- 5. The nucleus of a helium atom ejected during radioactivity stopped by a piece of paper.
- 6. A particle like an electron, but with positive charge.
- 7. High-energy particle with no charge goes through lead but is stopped by water or concrete.
- 9. High-speed, high-energy electrons or positrons emitted from the nucleus stopped by thin wood or metal plates.
- 10. An element with a radioactive isotope essential for the human body and contained in many foods.
Down
- 1. The international unit measuring the radiation effect on the human body equivalent to 100 REMs.
- 2. A radioactive element contained in Earth’s soils.
- 4. One of the more radioactive fruits providing 0.1 microSieverts of radiation from the isotope Potassium-40.
- 8. Penetrating high-energy, photons emitted during radioactivity best stopped by thick metal plates.