1. Electromagnetic Spectrum
     

3. Electromagnetic waves
Produced by the movement of electrically charged particles
Can travel in a “vacuum” (they do NOT need a medium)
Travel at the speed of
light
Also known as EM waves

4. Electromagnetic radiation waves
Waves are three dimensional
Waves vibrate in all planes around a center line.
The waves have high points called “crests.”
Waves also have low points called “troughs.”
*The distance from one crest to the next crest is called a “wavelength.”
*The number of waves passing a given point in one second is called the “frequency.”
The vertical distance between a peak(crest) and a valley is called the “amplitude.”
wavelength

5. Peaks are also called crests!
This is an example of a transverse wave!
Peaks are also called crests!

6. ? ? ?
Prompt students to guess what the teal box, then the blue box, is hiding. (Wavelength, Amplitude) Then the red box and yellow box (trough and crest) ?

7. Remember radio waves are long…and gamma rays are small
Radio-TV -Microwave- Infrared - VISIBLE -Ultraviolet -X-rays - Gamma- Cosmic

8. Radio (Longest electromagnetic waves)
Emitted by
Astronomical Objects
Radio Station Transmitters
Detected by
Ground based radio telescopes
*If you turn on a radio, it will convert the radio wave energy into sound energy.

9. Radio waves Wavelength: 100 km – 100 m Uses: TV broadcasting
AM and FM broadcast radio
Avalanche beacons
Heart rate monitors
Cell phone communication
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

10. Microwave Emitted by: Detected by Gas clouds collapsing into stars
Microwave Ovens
Radar Stations
Cell Phones
Detected by
Microwave Telescopes
Food (heated)
Cell phones
Radar (systems)

11. Microwaves Wavelengths from 1 mm- 1 m Uses: Microwave ovens
Bluetooth headsets
Broadband Wireless Internet
Radar
GPS
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

12. Infrared (Heat or Thermal) Are you a source of infrared? YES you are!
Emitted by
Sun and stars (Near)
TV Remote Controls
Food Warming Lights (Thermal)
*Everything at room temperature or above,=HEAT
Detected by
Infrared Cameras
TVs, VCRs,
Your skin

13. Infrared Radiation Wavelengths: 750nm-1mm Uses: Night vision goggles
Remote controls
Heat-seeking missiles
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

14. Visible Each color is a different size wave
Visible Each color is a different size wave. Red the longest & violet the shortest
Emitted by
The sun and other astronomical objects
Laser pointers
Light bulbs
Detected by
Cameras
(film or digital)
Human eyes
Plants (red light)
Telescopes
RoyG.Biv

15. Visible light
Only type of EM wave able to be detected by the human eye
Violet is the highest frequency light
Red light is the lowest frequency light
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

16. Visible light Wavelength: 390nm – 750nm Uses: Enables us to see things
Photosynthesis in plants

17. Ultraviolet Sunburn / black light
He can get skin cancer!
Emitted by
Tanning booths (A)
The sun (A)
Black light bulbs (B)
UV lamps
Detected by
Space based UV detectors
UV Cameras
Flying insects (flies)

18. Ultraviolet Wavelength: 10nm – 400nm Uses: Black lights
Sterilizing medical equipment
Water disinfection
Security images on money
There is one more UV slide…

19. X-ray Emitted by Detected by Astronomical objects X-ray machines
CAT scan machines
Older televisions
Radioactive minerals
Airport luggage scanners
Detected by
Space based X-ray detectors
X-ray film
CCD detectors

20. X-rays Wavelength: 0.01nm – 10 nm Uses: High energy Medical imaging
Airport security
Inspecting industrial welds
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

21. Gamma Ray (Short electromagnetic waves but more energetic)
Emitted by
Radioactive materials
Exploding nuclear weapons
Gamma-ray bursts
Solar flares
Detected by
--Geiger counters
Gamma detectors and astronomical satellites
Medical imaging detectors

22. Gamma Rays Smallest wavelengths, highest energy EM waves
Wavelengths: less than 0.01nm
Uses
Food irradiation
Cancer treatment
Treating wood flooring
Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

23. How big are the waves? A great question! Radio waves= (Buildings to
human size);
Microwaves
(Humans-beetles);
Infrared waves
(Eye of a needle);
Visible waves
(microscopic size)!
WOW! All the rest are the size of molecules, atoms, atomic nuclei and smaller.. See the next slide for more.

24. Relative Size

27. Extention
Catch a Wave – Discovery Education Exploration