1. 4 th Period SI EM Spectrum 8 Jan 2009 NOTE: Infrared Rays are missing. The “infrared group” never turned in as of 3:15 Friday. This group will feel bad next class period. You are still responsible for knowing “infrared” material. Don’t memorize numbers.

2. Radio Waves =The longest wave on the electromagnetic spectrum Frequency Range = <1x10 9 Uses for radio waves Diagram of the electric and magnetic fields of Radio Waves emanating from a radio transmitting antenna.

3. Radio waves were discovered by James Clerk Maxwell in 1865. Radio waves can be longer than a football field or as short as a football. The ignition of the spark plugs in gasoline-powered cars can interfere with radio waves. Radio astronomy is the science of using radio waves to look at the universe.

4. Gamma Rays Facts Gamma rays have the highest energy (frequency) of all electromagnetic waves. Therefore, they have the smallest wavelengths. The wavelengths can be as short as 10 14 meters. Gamma rays can help treat against cancer by killing diseased cells. But, gamma rays can also create cancer cells because of the radiation.

5. Gamma Rays pictures Gamma rays have the greatest frequency and smallest wavelength.

6. Gamma Waves Highest frequency waves on electromagnetic scale. Can change cells to cancer cells but can also kill cancer cells. Some gamma ray flares from magnetars are so powerful that even though they occur thousands of light years away, they measurably affect the upper layers of the Earth’s atmosphere.

7. Gamma Rays Wave Intensity on the Electromagnetic Spectrum  Highest energy wave in the electromagnetic spectrum. Frequency; from 10 19 to 10 22 Hz Gamma Rays in Space

8. Ultraviolet Light Definition: Ultraviolet waves are waves that have wavelengths shorter than visible light but longer than x- rays. Frequency Range: 7.5x10^14 – 3x10^16 Hz Nine percent of the energy emitted by the sun is ultraviolet light.

9. 1.A positive effect of UAB exposure is that it induces the production of vitamin D in the skin. 2.UVA causes aging of the skin, DNA damage, and possibly skin cancer. 3.UVB causes burns to the skin and can damage the eyes if exposed.

10. In the visible light spectrum we see these waves as the colors of the rainbow. Each color has a different wavelength. When all the waves are seen together they form white light. Red visible light has the longest wavelength.

11. Definition- Electromagnetic waves we can see. Frequency range- 4.3x10 14 -7.5x10 15