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Homework Help: Fluid dynamics (2)

  1. Feb 15, 2014 #1
    1. The problem statement, all variables and given/known data

    If the pressure reading of your Pitot tube is 17.0 mm Hg at a speed of 150 km/h, what will it be at 700 km/h at the same altitude?

    2. Relevant equations

    The only eq I could think if is p = p2+ 1/2 density (v2^2 - v1^2)

    But I don't know the density

    3. The attempt at a solution

    So I pretty much get stuck in the beginning, any help will be nice

  2. jcsd
  3. Feb 15, 2014 #2


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    What would the reading be at 0km/h? What equations do you now have?
    (Note: I'm assuming the equation you quoted is appropriate. To check that I'd need to do some research.)
  4. Feb 15, 2014 #3
    At the tip of the pitot tube, the velocity is zero. So you are measuring the stagnation pressure. If the density doesn't change between the two cases, how does the stagnation pressure depend on the approach velocity?

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