1. © Copyright Pearson Prentice Hall Slide 1 of 18 Radiation in Your Life In a smoke detector, radiation from the Americum nuclei ionizes the nitrogen and oxygen in smoke-free air, allowing a current to flow. When smoke particles get in the way, a drop in current is detected by an electronic circuit, causing it to sound an alarm. You will learn about some of the other practical uses of radiation. 25.4

2. © Copyright Pearson Prentice Hall Radiation in Your Life > Slide 2 of 18 Detecting Radiation - three devices used to detect radiation 25.4

3. Slide 3 of 18 © Copyright Pearson Prentice Hall Radiation in Your Life > Detecting Radiation Geiger counters scintillation counters film badges are commonly used to detect radiation. 25.4

4. Slide 4 of 18 © Copyright Pearson Prentice Hall Radiation in Your Life > Detecting Radiation Radiation can produce ions which can then be detected, or it can expose a photographic plate and produce images. 25.4

5. Slide 5 of 18 © Copyright Pearson Prentice Hall Radiation in Your Life > Detecting Radiation Geiger Counter A Geiger counter uses a gas-filled metal tube to detect radiation. 25.4

6. Slide 6 of 18 © Copyright Pearson Prentice Hall Radiation in Your Life > Detecting Radiation Scintillation Counter A scintillation counter uses a phosphor-coated surface to detect radiation. 25.4

7. Slide 7 of 18 © Copyright Pearson Prentice Hall Radiation in Your Life > Detecting Radiation Film Badge A film badge consists of several layers of photographic film covered with black lightproof paper, all encased in a plastic or metal holder. 25.4

8. © Copyright Pearson Prentice Hall Radiation in Your Life > Slide 8 of 18 Using Radiation radioisotopes used in medicine, crime labs, and museums 25.4

9. Slide 9 of 18 © Copyright Pearson Prentice Hall Radiation in Your Life > Using Radiation Neutron activation analysis is a procedure used to detect trace amounts of elements in samples. Neutron activation analysis is used by museums to detect art forgeries, and by crime laboratories to analyze gunpowder residues. 25.4

10. © Copyright Pearson Prentice Hall Slide 10 of 18 Radiation in Your Life > Using Radiation Radioisotopes can be used to diagnose medical problems and, in some cases, to treat diseases. 25.4

11. Slide 11 of 18 © Copyright Pearson Prentice Hall Radiation in Your Life > Using Radiation This scanned image of a thyroid gland shows where radioactive iodine-131 has been absorbed. 25.4

12. © Copyright Pearson Prentice Hall Slide 12 of 18 25.4 Section Quiz. 1. Ionizing radiation can remove _______ from atoms.

13. © Copyright Pearson Prentice Hall Slide 13 of 18 25.4 Section Quiz. 2.Which of the following is NOT a device used to detect radiation?

14. © Copyright Pearson Prentice Hall Slide 14 of 18 25.4 Section Quiz. 3.Choose the correct words for the space. When a tumor is treated by radiation, more cancer cells than normal cells are killed because cancer cells ____________ than normal cells.

15. © Copyright Pearson Prentice Hall Slide 15 of 18 25.4 Section Quiz. 4.How do scientists detect thyroid problems?