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Electromagnetic wave cancellation

  1. Jun 27, 2010 #1
    Hey guys i have a question about EM waves.

    I know with sound waves that if you emit a inverted wave of the same amplitude it cancels the effect. Now i know that sound waves are air pressure but does the same principle work for EM waves?
    If so what effects would be experienced?
  2. jcsd
  3. Jun 27, 2010 #2
    Yes this is destructive interference and it also occurs for both EM/acoustic waves.
  4. Jun 27, 2010 #3
    Yes the same can happen for EM waves , constructive and destructive interference ,
    This happens in the double slit experiment with light when the light passes through the double slit it interferes with itself and we get bright and dark spots on the screen , And this can also happen with just 1 slit also , and this can happen with electrons too and other particles .
  5. Jun 27, 2010 #4


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    When I was in high school, more years ago than I like to remember, a common physics experiment was this- take two microscope slides placed flat against each other, and rap a rubber band tightly at one end. That causes the slides to be pinched together at that end so that there is a slight "wedge" of space between them. Monochromatic light will reflect off both the inner face of the first slide and the outer face of the second slide at very slightly different distances so that the two waves are just slightly out of "phase". You will see bands of light and dark showing where the two waves reinforce or interfere.

    (You should use monochromatic light so the differing wavelengths of white light will not cause confusion.)
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