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Light/radio waves radiate in all direction

  1. Aug 19, 2009 #1
    how a light is able to focused in one direction?
    after the light gets reflected in the reflectors or dishes it is out in the open space and then it should be radiating in all direction

    same is in the case of working principle of radar and rotating signal from VOR(vhf omni-directional radio range) in which the aircraft recieve the rotating signal only when it is directed towards it.

    thanks in advance.
  2. jcsd
  3. Aug 19, 2009 #2
    All waves follow the laws of reflection.A single wave does not split up(I'm not sure about this reading an argument in QM)
    What you might be interested in here is diffusion of waves by absobers and transmitters(for eg, sound transferred to the handle of a tuning fork propogates in all directions perpendicular to the length of the vibrator)
    Last edited: Aug 19, 2009
  4. Aug 19, 2009 #3
    yes and thxx.
    what is it that split, if u could explain further.
  5. Aug 19, 2009 #4


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    Diffusion is the scattering of incident light into all directions. Specular reflection is when the incident light is reflected at an angle equal to the angle of incidence. That is, a straight ray strikes a surface and a straight ray is reflected back. Any time we wish to focus a wave we simply use a scatterer that will have specular reflections.
  6. Aug 19, 2009 #5
    also if u can explain how the light from a flashlight focused in a different direction reaches our eyes
  7. Aug 19, 2009 #6
    Born2bwire: doesn't a ray radiate in all direction as after all its a wave
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