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Radio wavelength

  1. Jan 12, 2007 #1
    Are the length of radio waves relative to the scale and gravitational force of origin?

    In other words, if one increases, the scale of the earth and total solar system by 10 times when this planet emits human produced radio waves, will the wavelength also be 10 times larger?
     
    Last edited: Jan 12, 2007
  2. jcsd
  3. Jan 12, 2007 #2

    mathman

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    Radio wavelengths are a property of the transmitter - the size of the earth and its gravity strength are irrelevant.
     
  4. Jan 12, 2007 #3
    If you increase the size of the transmitter by 10, will the wavelength also increase by 10?
    Gravitational force does not influence wavelength?
     
  5. Jan 12, 2007 #4

    chroot

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    If you increase the frequency of the electrical signal driving the antenna by a factor of 10, you will decrease the wavelength of the resulting EM wave by a factor of 1/10. Changing the size of the antenna does not change the wavelength of the resulting EM wave, it only changes the antenna's radiative efficiency.

    And no, gravity is in no way related to electromagnetic radiation.

    - Warren
     
  6. Jan 12, 2007 #5
    Thanks Warren
    So if you increase the antenna by 10 it decrease the wavelength by 1/10.
    As the size of the antenna goes up the wavelength goes down.
    Is it the same in reverse?
    I assume the answer is yes.
    Are we able to translate all forms of radio wavelengths or are there some that we are not because we are restricted by size and cannot view?
     
  7. Jan 12, 2007 #6

    chroot

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    No, Entity, that's not at all what I just said. Please read my response again more carefully.

    - Warren
     
  8. Jan 12, 2007 #7
    sorry I got you now
    Are we able to translate all forms of radio wavelengths or are there some that we are not because we are restricted by size and cannot view?
     
  9. Jan 12, 2007 #8

    chroot

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    I have no idea what you mean by "translate." Do you mean, can we use antennas to send and receive all frequencies of electromagnetic radiation?

    The answer is yes, if you define an "antenna" as any device intended to emit or detect electromagnetic radiation. Standard dipoles work well up to microwave frequencies, after which we need to use microwave horns and other exotic technologies. Above microwaves, up into the infrared and visible spectrum, another set of technologies come into play. Above ultraviolet, yet another, and so on. There is no single existing kind of "antenna" that can generate any arbitrary wavelength from radio to gamma rays, however.

    The whip-like pieces of metal usually meant by the word "antenna" are only capable of emitting and detecting electromagnetic radiation over the part of the EM spectrum called "radio."

    - Warren
     
  10. Jan 12, 2007 #9
    Thanks For your time I understand
     
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