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Force of drag Fd=?

  1. Sep 8, 2010 #1
  2. jcsd
  3. Sep 8, 2010 #2


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  4. Sep 8, 2010 #3
    Re: Drag


    http://en.wikipedia.org/wiki/Drag_(physics [Broken])

    There are two regimes, turbulent (high Reynold's number) and linear (Stokes) drag.

    Bob S
    Last edited by a moderator: May 4, 2017
  5. Sep 8, 2010 #4
    Re: Drag

    I meant how Fd is related to:

    (Reynolds Number)=(Inertial Forces)/(Viscous Forces)
  6. Sep 8, 2010 #5


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    Re: Drag

    Did you not read the link I gave you?

  7. Sep 8, 2010 #6
  8. Sep 8, 2010 #7
    Re: Drag

    "...For the gas, the magnitude depends on the viscosity of the air and the relative magnitude of the viscous forces to the motion of the flow, expressed as the Reynolds number..."

    So? We have:
    Re=(inertial forces)/(viscous forces)

    At wiki it says
    " Note that this (Re) is equal to the ratio between...which is the drag (up to a numerical factor, half the drag coefficient)..."

    So, Fd=(inertial forces)?
    Should't it be Fd=(inertial forces)+(viscous forces)?

    Both wrong? Any site making all this a bit clear?
    Last edited: Sep 8, 2010
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