Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Aerodynamic power

  1. Jan 21, 2012 #1
    1. The problem statement, all variables and given/known data
    aerodynamics question. Power P to fly a plane.
    Has P = Mass 3/2 do not know if this means square M by 3/2? that is how i take it to be then you divide this by √S which is cross section of wing.

    figures are M = 124.6kg 3/2 divided by S = √ 36m Squared
    solution comes up with M 1389/S 6m = 231.5kg m to power of -1
    I do not know how to get to figure of 1389?


    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Jan 21, 2012 #2

    gneill

    User Avatar

    Staff: Mentor

    (124.6)(3/2) ≈ 1391

    If the author used logs with only a few decimal places, or a slide rule, to work out the answer it could have ended up as 1389. Is this example from a book? If so, what's the date of publication?
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook