1. Electromagnetic Radiation
8th Grade
     B. Burel & R. Lee

2. EM Waves
Electromagnetic waves are actually made up of 2 parts: an electric force field and a magnetic force field. That’s where the name electo…magnetic comes from!
An electromagnetic wave is produced by vibrating electrical and magnetic charges.
In fact, all waves are produced by something vibrating.

4. Waves in space?
Most waves, like sound waves or oceans waves must have a medium (some form of matter) through which they travel.
However, electromagnetic waves can travel with or without a medium. This allows EM waves to travel through the empty vacuum of space. Sunlight and ultraviolet radiation that both light and heat our planet, travel millions of miles from the Sun to Earth by EM waves.

5. EM Waves are transverse waves
All electromagnetic waves are transverse waves. Transverse waves move up and down or side to side at repeated right angles in the direction of the wave’s energy.

6. Parts of a transverse wave?
Frequency
Prompt students to guess what the teal box, then the blue box, is hiding. (Wavelength, Amplitude) ?

7. Electromagnetic waves
All EM waves travel at the speed of
light which is 300 million m/s.
The Sun is 150 gigameters or 95 million miles away from the Earth. Traveling at the speed of light, it take sunlight 8 minutes and 20 seconds to reach Earth….WOW!

9. The Electromagnetic Spectrum

10. Radio waves Longest wavelength EM waves 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

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 Radiation Wavelengths in between microwaves and visible light
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

13. Visible light
Only type of EM wave able to be detected by the human eye (ROY G. BIV)
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

14. Ultraviolet Shorter wavelengths than visible light Uses: Black lights
Sterilizing medical equipment
Water disinfection
Security images on money
There is one more UV slide…

15. Ultraviolet (cont.) UVA UVB and UVC Energy Highest of UV waves
Lower than UVA
Health risks
Can cause DNA damage, leading to skin cancer
Responsible for sunburn
No serious risk for DNA damage.
Can cause Vitamin A deficiency.
Table will fill in from left to right, top to bottom as you advance through. Click the little rainbow box in the top right corner to return to the overview EM spectrum diagram

16. X-rays Tiny wavelength, high energy waves Uses: 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

17. Gamma Rays Smallest wavelengths, highest energy EM waves 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

18. Video Wrap-Up