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Attenuation coefficient of water

  1. Sep 23, 2012 #1
    I have read that the attenuation of water (for ultrasound) is 0.0472 Np m–1
    (MHz)–2.

    What is this in dB/cm/MHz^-2 ? What is Np?

    thanks
     
  2. jcsd
  3. Sep 23, 2012 #2

    davenn

    User Avatar
    Science Advisor
    Gold Member

    Np = Neper, its another way of describing attenuation loss

    see this wiki for a longer explanation
    http://en.wikipedia.org/wiki/Neper

    there's sure to be converters on the net to do the conversion between Neper and dB
    Google is your friend :)

    Dave
     
  4. Sep 24, 2012 #3
    thanks :)
     
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