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Homework Help: Is this Wavelength answer correct?

  1. Sep 16, 2007 #1
    The question is: Calculate the wavelength of a 1.5 MHz sound wave that is being transmitted through soft tissue. (This is Ultrasound physics, if you are wondering.)
    formula used: wavelength = velocity (1540 m/s) divided by 1.5 MHz

    MHz changes to 1.5 x 10^6

    so I have: 1540m/s / 1.5 x 10^6 1/s=10.27 x 10^-4m or 10.27mm


    Is this correct? I'm worried about my conversion---I tend to mess up the most simple conversions.

    Thx!

    Kathy
     
  2. jcsd
  3. Sep 16, 2007 #2

    Astronuc

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    Staff Emeritus
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    10.27 x 10-4m is correct, however it is not 10.27 mm (which is ~0.4 inch).

    Ultrasound has short wavelengths, usually < 1 mm.

    So 1 mm is 10-3 m.

    10.27 x 10-4m = 1.027 x 10-3m = 1.027 mm, which is long for UT.
     
  4. Sep 16, 2007 #3
    Thank you! Those darned old decimals get me every time!!!!
     
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