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Homework Help: Power, Force, Velocity and Acceration

  1. Jan 8, 2006 #1
    Is the statement below wrong?

    1. Assume a car is travelling on a frictionless landscape. The car engine has a constant power,P.
    2. The engine produces a force, which equals to the total resultant force act upon the car.
    3. F=ma. So the car should be travelling in acceration.
    4.Throught time, the velocity increase as there is acceration.
    5. Since P is constant, and P=Fv, F shall decrease as v increase. The total resultant force shall decrease throughout time.
    6. Acceleration will decrease.
  2. jcsd
  3. Jan 9, 2006 #2


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    This cannot be, in a "frictionless landscape" the car will not move.
    Given 2, 3 is incorrect. If the force produced by the engine equals the other forces (I thought this was a frictionless landscape????) Then there is on net force therefore no acceleration. At best, if we ignore, 1. the car moves at a constant velocity.
    No motion, no velocity, no acceleration. OR Constant velocity, no acceleration.
    Please explain P=Fv ? What is this? Where did it come from? What does it mean?
    There are so many incorrect statements that the last has no meaning.
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