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Electromagnetic radiation

  1. Nov 26, 2007 #1
    I was just wondering why is the sunlight called the electromagnetic radiation. I posted this on other science forum but got no satisfactory answers. MY friends even suggested me to look at some detail on quantum mechanics and told me to look on quantum nature and refer http://www.physics-physicsdiscussion.blogspot.com . I want to know if this is helful site

  2. jcsd
  3. Nov 26, 2007 #2


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    An oscilating magnetic field generates an oscilating electrical field. That oscilating electrical field in turn generates an oscilating magnetic field. If the two are set into motion together, they are self-perpetuating; kind of a "chicken-and-the-egg" situation. These types of fields, consisting of oscilating electrical and magnetic fields sustaining each other, are called "electromagnetic," and they include visible light, infrared light, heat, ultraviolet, radio, gamma... the whole range of what we call the "Electromagnetic spectrum."

    (Didn't check the link; maybe somebody else might?)
  4. Nov 27, 2007 #3
    I suggest u to read faraday-Maxwell-Einstein's works. you'll probably find out that it is correct to speak about a tensor field F (Electromagnetic) instead of two vector's field E and B. This was the firts unified field theory.
    Jackson "Classical Electrodynamic" is a good reference.
  5. Nov 27, 2007 #4


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    Er... Jackson's text is not a "good reference" for someone who does not know why light is an electromagnetic wave.

    I suggest trying something more elementary, such as the Hyperphysics webpage.


    Light is an electromagnetic wave because it has an oscillating E and B vectors and is obtained by solving the Maxwell equation, resulting in a differential equation having a "wave" form.

    The nature of this question has nothing to do with quantum physics, so this thread has been moved to the Classical Physics section.

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