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C is only a component of light speed?

  1. Nov 2, 2005 #1
    I'm just thinking that since light is an electromagnetic wave, it must move sinusoidally. So, wouldn't it just be going forward at the speed of "c", while the wave itself would be going up and down as well? And if that's the case, wouldn't the actual speed of the photons be much faster if the wave was more stretched out? I'll try to draw what I mean:
    Code (Text):
              c -->
      ___              ___
     /    \           /     \    
    /      \         /       \    
            \       /         \    
             \___/           \
    I may be completely wrong on this, but if so, why?
  2. jcsd
  3. Nov 2, 2005 #2


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    You probably do not realize that what is "oscillating" is not photons, but rather the electric field that is being carried by each of these photons. The photons themselves do not wiggle up and down in space.

  4. Nov 2, 2005 #3
    Ahh. Well then... I guess I learned something. Thanks.
  5. Nov 2, 2005 #4
    It took me until I entered College physics for the first time to actually figure that out. High School physics books are really bad at showing you that, they show you this little picture of light travelling sinusoidally, never actually tell you that the y dimension in that graph is not a distance, but the intensity of the electric (or magnetic) field as the photon travels in the x direction.

  6. Nov 3, 2005 #5
    I think you mean amplitude, not intensity.
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