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Relative Size Of Electro-Magnetic Spectrum

  1. Jul 19, 2013 #1
    I Watched A Video . In Which , It's Mentioned That The

    Relative Size Of..

    Gamma Rays - Atomic Nucleus
    X-Rays - Atom
    Ultra-Violet Rays - DNA
    Visible Light - Bacteria
    Radio Waves - Mountain Ranges

    What's Mean By Relative Size ? I'm Confused Alot !

    Thanks Alot In Advance For You Help
  2. jcsd
  3. Jul 19, 2013 #2


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    Science Advisor
    Gold Member

    It simply means that e.g. the wavelength of gamma rays is similar to the typical radius of atomic nuclei.
  4. Jul 20, 2013 #3
    Thanks Alot

    Thanks Alot For Your Help :)

    I Have Another Doubt . Does It Mean The Radius or Diameter ? Because Wavelength Of Gamma Rays is 10(power -15) which is the diameter of nucleus .so you're referring to diameter ... (right?)
  5. Jul 20, 2013 #4


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    Staff: Mentor

    When we make crude comparisons like this, we usually don't try to be more exact than the nearest power (exponent) of 10, in which case a factor of 2 or 1/2 is not significant.
  6. Jul 20, 2013 #5


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    Staff: Mentor

    Gamma rays have a broad spectrum, with roughly 10-15m as maximal wavelength and without a minimal wavelength - and the first border is not very strict, different scientists use different values.

    Nuclei have different radii, too - an uranium nucleus (92 protons and ~145 neutrons) is larger than a hydrogen nucleus (a single proton).
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