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EM effects

  1. Oct 25, 2013 #1
    What effect does water have on electromagnetic waveforms?

    Does metal attract or reflect EM waveforms (specifically rf)?
     
  2. jcsd
  3. Oct 25, 2013 #2
    Attracts gravitationally.
     
  4. Oct 25, 2013 #3
    so water absorbs (Microwave spectrum), correct? Is it correct to say that water distorts or just absorbs?

    What exactly is meant by metal attracts gravitationally?
     
  5. Oct 25, 2013 #4

    ZapperZ

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    This is a bit puzzling.

    What exactly do you mean by "electromagnetic waveforms"?

    Secondly, have you heard of refraction and snell's law?

    Thirdly, metals do not attract EM waveforms. Metals and dielectrics impose boundary conditions to EM radiations.

    It would help if you provide some context to these questions, and also background info on what you can understand.

    Zz.
     
  6. Oct 25, 2013 #5
    So, what I mean is in the realm of wifi, which I always thought to be rf. Since 2.4GHz is actually in the Microwave "region" if you will, of the electromagnetic spectrum, isn't that the correct way to refer to the actual transmission medium?

    Specifically:
    What exactly do you mean by "electromagnetic waveforms"? I thought this was the correct way to refer to any freq. whether it is rf, Microwave, UHF, etc.

    Secondly, have you heard of refraction(yes, as it applies to light. Is it the same for rf/Microwaves?) and snell's law? I will research this.

    Thirdly, metals do not attract EM waveforms. Metals and dielectrics impose boundary conditions to EM radiations. So rf bounces off of metal? Why then do they use metal for antennas to receive rf?
     
  7. Oct 25, 2013 #6

    ZapperZ

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    There's a lot of mixed words and terminology here.

    First of all, there is no "transmission medium".

    Secondly, a "waveform" is typically referred to the SHAPE of the wave, ie wave profile. You are referring to, if I'm guessing correctly, the electromagnetic wave/radiation.

    Thirdly, light, as in visible light, is part of the electromagnetic spectrum, which includes X-rays, microwaves, radio waves, gamma rays, infrared, etc.

    Finally, when I say metallic and dielectrics impose boundary conditions on EM radiation, there is nothing in there that automatically ruled out transmission, reflection, absorption, etc. I have no idea before what context you are asking the question, so you got a generic answer.

    If you are asking about antenna for transmission and reception, this has nothing to do with metals "attracting" EM radiation. It has more to do with metals having conduction electrons that are able to respond to external EM field or applied potential.

    Zz.
     
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