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I Unit of Specific Speed

  1. Aug 2, 2016 #1
    Hi
    Specific Speed is defined as:
    Ns=N(Q^0.5)/(H^.75)
    How Dimensional Analysis of it can be done? Unit of N is 1/sec and Ns is unitless. Then Dimension of Q^0.5 must be equal to dimension of H^0.75. It seems no to be equal.
    Please explain it.
     
    Last edited: Aug 2, 2016
  2. jcsd
  3. Aug 2, 2016 #2

    Nidum

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    What is your question ?
     
  4. Aug 2, 2016 #3
    Please analyse the formula dimensionally.
     
  5. Aug 2, 2016 #4

    Nidum

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    Your formula is only pseudo dimensionless . The calculated Ns number is only valid for a specific system of units .

    The proper dimensionless formula has a g in the denominator . Explained reasonably well in Wikipedia .
     
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