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Top Speed Equation?

  • 10-08-2004 10:40pm
    #1
    Fabritzo
    Registered Users, Registered Users 2 Posts: 1,500 ✭✭✭


    How does one approximate the top speed of a 100 kilowatt car the weighs 1500kg with drag coefficient of 0.3. Again, just an aprroximation please, no crosswinds, heat losses etc.

    Thanks


Comments

  • #2
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 94,272 Mod ✭✭✭✭Capt'n Midnight


    If you are ignoring all fiction apart from drag through still air then weight is irrelevant.

    If you are trying to calculate the DRAG then the surface area is necessary.


  • #3
    Fabritzo
    Registered Users, Registered Users 2 Posts: 1,500 ✭✭✭Fabritzo


    I thought that was accounted for by the cd but, approximating the car to be 1.5metre wide and 1 metre high


  • #4
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 94,272 Mod ✭✭✭✭Capt'n Midnight


    CD is a ratio between the Drag caused by the shape and the Drag caused by the surface friction. A properly designed aerofoil can have a drag less than a cylinder a tenth of it's thickness.

    Besides I always thought CD was velocity dependent.

    Hint: you are looking for an equation. Stokes ??


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