Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie
Hi all! We have been experiencing an issue on site where threads have been missing the latest postings. The platform host Vanilla are working on this issue. A workaround that has been used by some is to navigate back from 1 to 10+ pages to re-sync the thread and this will then show the latest posts. Thanks, Mike.
Hi there,
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest

Top Speed Equation?

  • 10-08-2004 11:40pm
    #1
    Fabritzo
    Registered Users, Registered Users 2 Posts: 1,521 ✭✭✭


    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: 92,550 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: 1,521 ✭✭✭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: 92,550 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 ??


Advertisement