1. Electromagnetic Waves Objectives
Know the names of each type of wave.
Know the order of the waves according to the wavelength/frequency
Know what each of the waves are used for
Know that all EM waves can travel through matter and empty space
Know that all of the EM waves travel at the speed of light

2. Electromagnetic Waves
Electromagnetic Waves
Electromagnetic waves (radiant energy) – waves that can travel through empty space and through matter. All EM waves travel at the speed of light.

3. All matter produces EM waves, and therefore, radiant energy.

4. Electromagnetic Spectrum
Longer wavelengths
Lower frequencies
Lower energy
Shorter wavelengths
Higher frequencies
Higher energy
wave
Light
Roman Men Invented Very Unusual X-Ray Guns

5. Electromagnetic Spectrum
Longer wavelengths
Lower frequencies
Lower energy
Electromagnetic Spectrum
Higher frequencies
Higher energy
wave
Light
-Used for communi-cation
-Radio stations
-Television stations
-Used for communic-ation
-Can carry more info than radiowaves
-Radar guns
-GPS
-Cellphones
-Microwaves
-Vibrating molecules in all matter give off infrared waves
-Thermal cameras detect infrared waves
-Waves carry enough energy to cause chemical reactions
-Causes sunburns, possibly skin cancer
-UV Wand - dries adhesives
-Tanning Beds
-Can pass through skin and muscles, but not bone
-Airport Scanners
-Produced when the nucleus of an atom breaks apart or changes
-PET scans
-Nuclear reactions
-Destroys diseased cells

6. Used for communication
Radiowaves
Used for communication
Radio stations
Television stations

7. Microwaves Used for communication Can carry more info than radiowaves
Radar guns
GPS (Global Positioning Systems)
Cellphones
Microwaves

8. Infrared Radiation
Vibrating molecules in all matter give off infrared waves
Thermal cameras detect infrared waves
The heat that we feel from sunlight, a fire, a radiator or a warm sidewalk is infrared. Although our eyes cannot see it, the nerves in our skin can feel it as heat.

9. Thermal Imaging - Before & After 15 minutes of Talking on Cell Phone

10. Temperature analysis with infrared photographs can be used for medical reasons. Highly active areas or areas of infection can be detected easily.

11. Some animals can "see" in the infrared
Some animals can "see" in the infrared. Snakes in the pit viper family (e.g. rattlesnakes) have sensory "pits," which are used to detect infrared light. This allows the snake to find warm-blooded animals (even in dark burrows), by detecting the infrared heat that they radiate.

12. Old Faithful Geyser
Old Faithful is the most frequently erupting large geyser in Yellowstone National Park. A geyser is a hot spring which erupts periodically.

13. Geysers in Yellowstone National Park

14. Bubbling Mudpots
Mudpots are hot springs which do not have much water.

15. ELK

16. Forest

19. Visible Light

20. Ultraviolet Waves
Waves carry enough energy to cause chemical reactions
Causes sunburns, possibly skin cancer

21. Ultraviolet Waves
UVA – skin aging, eye damage, can suppress the immune system. (does not cause burn)
UVB – causes burns, snow blindness, known as carcinogen
UVC – absorbed by ozone layer, most dangerous

22. Ultraviolet Radiation
UV Wand – dries adhesives
UV Nail Polish Dryer

23. Ultraviolet Radiation
Tanning Beds – UVA & some UVB rays

24. X-Rays
Can pass through skin and muscles, but not bone

25. X-Rays
Air port scanners

26. Gamma Rays
Produced when the nucleus of an atom breaks apart or changes
PET scans
Nuclear reactions
Destroys diseased cells

27. QOD#21 Which three types of EM waves are emitted from the sun?
QOD#21
Which three types of EM waves are emitted from the sun?
Ultraviolet waves
Visible light waves
Infrared waves