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Homework Help: Velocity and Acceleration

  1. Apr 26, 2010 #1
    1. The problem statement, all variables and given/known data
    a) A 3100 kg car can accelerate with a maximum acceleration of 3.0 m/s2.
    How long will it take this car to go from a velocity of 20 m/s to 40 m/s?

    b) If there is a 4000 N force do to air friction opposing the car's motion, what is the strength of the force responsible for the car's acceleration?

    c) What object exerts the force that accelerates the car?

    2. Relevant equations

    3. The attempt at a solution
    a) I got an answer of 6.67sec.

    b) I got an answer of 9700 N.

    c) The tires? Because of friction?
    Last edited: Apr 26, 2010
  2. jcsd
  3. Apr 26, 2010 #2


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    What causes the car to move in the first place is what I think they are asking for part c.
  4. Apr 27, 2010 #3
    The road?
  5. Apr 27, 2010 #4


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    Or it could be the engine causing the tires to rotate.
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