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Homework Help: Forces car of mass question

  1. Mar 19, 2007 #1
    i have this question for an engineering science assignment, and cant remember how to work it out, any help would be greatly appreciated.

    A car of mass 1500kg has a max speed of 144km/h up an incline of 1 in 49 against a frictional resistance of 500N. Calculate the power of the engine.
  2. jcsd
  3. Mar 19, 2007 #2
    Neglecting the usual frictional losses in the engine and drivetrain, air resistance, etc, which reduce auto efficiency to about 25%, it would seem at a steady state where acceleration=0, whatever force being generated is just equal to the opposing gravitational force and frictional force. I would think then that you need to look at the displacement, both vertical and against friction to compute the work done by the engine. Hope thats a help as one is supposed to show work prior to any major assistance being given.
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