1. Chapter 3 The Electromagnetic Spectrum

2. Electromagnetic waves
transverse waves that have some electrical properties and some magnetic properties.
- consists of changing electric and magnetic fields
Electric fields: a region in which charged particles can be pushed or pulled.
Magnetic fields: a region in which magnetic forces are present.

3. Electromagnetic waves in motion

4. Electromagnetic Radiation
the energy that is transferred by electromagnetic waves
does not need a
medium.

5. Light: properties of both waves and a stream of particles.
Polarized Light: light that passes through a filter

6. Polarized Light

7. Photoelectric effect
the movement of electrons in a substance when light is shined on it.

8. Photoelectic energy
The photoelectric effect has practical applications in photoelectrical cells used for solar powered cars, and solar powered calculators.

9. Characteristics of EMS Waves:
all E.W. travel at the same speed
Each type of wave has a different wavelength
Each type of wave has different frequencies

10. Electromagnetic Spectrum:
the complete range of E.W. placed in order of increasing frequency

11. Clicking the little rainbow box at the top of each slide will bring you back to this one

12. Longest Wavelength Shortest Wavelength Lowest frequency ____Highest frequency Lowest Energy ____Highest Energy
Radio Microwave Infrared Visible UV Rays X-rays Gamma rays
light

13. Radio Waves E.W. with the longest wavelength and lowest frequencies
Uses:
radar: a system that uses reflected radio waves to detect objects and measure their distance and speed. TV broadcasting
AM and FM broadcast radio
Heart rate monitors
Cell phone communication

14. Microwaves Radio waves with a shorter wavelength Uses: Microwave ovens
Bluetooth headsets
Broadband Wireless Internet
Radar
GPS

15. Infrared Rays E.W. with wavelengths shorter than radio waves Uses:
Night vision goggles
Heat lamps
Infrared cameras
Remote controls
Heat-seeking missiles

16. Visible Light E.W. that you can see. - longest wavelength, red
- shortest wavelength, violet
- white light = mixture of colors (can be seen with the use of a prism)

17. Ultraviolet Rays
carry more energy b/c they have higher frequencies than visible light and shorter wavelength.
Uses:
Black lights
Sterilizing medical equipment
Water disinfection
Security images on money

18. X-Rays E.W. with more energy than UV rays. can penetrate most matter,
except bones (denser matter)
Uses:
Medical imaging
Airport security
Inspecting industrial welds

19. Gamma Rays
E.W. with the most amount of energy and highest frequency and the shortest wavelengths.
Uses
Food irradiation
Cancer diagnosis and treatment