Electromagnetic Waves

by Brennan Gould

Disturbances That Create EM Waves

Electromagnetic waves (EM waves) are created by the vibration of an electrical charge. They contain of magnetic and electrical components.

Contrasting EM Waves to Mechanical Waves

  • Electromagnetic waves don't need a medium in which to travel
  • Mechanical waves are typically slower than EM waves

Video

Radio Waves

  • Lowest frequency
  • Wavelength >1
  • Lowest energy
  • Used in Radios
  • Used in TV's

Microwave

  • Very low frequency
  • Wavelength = 1 to 10^-3
  • Very low energy
  • Used in microwaves
  • Helps astronomers see distant galaxies

Infrared

  • Mid-to-low frequency
  • Wavelength = 10^-3 to 10^-6
  • Mid-to-low energy
  • Used in night-vision goggles
  • Helps map dust in between stars

Visible Light

  • Mid frequency
  • Wavelength = 8 x 10^-7 to 4 x 10^-7
  • Mid energy
  • Used in light bulbs
  • Helps people see color

Ultra-Violate

  • Mid-to-high frequency
  • Wavelength = 3 x 10^-7 to 10^-8
  • Mid-to-high energy
  • Used by the sun
  • Used in tanning beds

X-Rays

  • Very high frequency
  • Wavelength = 10^-8 to 10^-12
  • Very high energy
  • Used by doctors to examine bones
  • Used by airport security to check bags

Gamma Rays

  • Highest frequency
  • Wavelength = <10^-12
  • Highest energy
  • Used to kill cancer cells
  • Used to kill bacteria in food
  • Fun Fact: Gamma radiation turned Dr. Banner into the Hulk in Marvel Comics