1 of 14

The Electromagnetic Spectrum

2 of 14

The Electromagnetic Spectrum

The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation

3 of 14

The EMS

The EMS consists of:

  1. Radio waves
  2. Microwaves
  3. Radar
  4. Infrared rays
  5. Visible light
  6. Ultraviolet rays
  7. X-rays
  8. Gamma rays

4 of 14

Electromagnetic Waves

Electromagnetic waves travel at the speed of light:

3.0 x 108 m/s

    • EMS waves do NOT need a medium to travel
    • Can travel in outer space/in a vacuum

5 of 14

Radio Waves

Used for long-distance communication

    • Lowest frequencies
    • Longest wavelengths

6 of 14

Microwaves

Used for communication and cooking

7 of 14

Radar

Short-length microwaves

RAdio Detection And Ranging Science

8 of 14

Infrared Radiation

Can’t be seen with the naked eye

Can be felt as heat

Frequency is slightly lower than red visible light

9 of 14

Infrared Radiation

10 of 14

Visible Light

The only portion of the EMS that we can see

    • Red is the lowest frequency (longest wavelength)
    • Purple is the highest frequency (shortest wavelength)

11 of 14

Ultraviolet Radiation

  • Frequency is slightly higher than violet visible light
  • Energy is great enough to kill living cells
  • Causes sunburn and skin cancer
  • Earth’s ozone layer deflects most of the sun’s harmful UV radiation

12 of 14

X-rays

  • Energy is great enough to pass through many materials
  • Pass through soft tissues like muscle and fat
  • Bones absorb x-rays

13 of 14

Gamma Rays

  • Highest frequency
  • Highest energy
  • Shortest wavelength
  • Can penetrate 3 m of concrete
  • Used in the treatment of some cancers

14 of 14