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Homework Help: How do you find the velocity with only the following given information?

  1. Jan 18, 2010 #1
    1. The problem statement, all variables and given/known data

    The coefficient of friction between a racecar’s wheels and the track is 1.0. The car starts from rest and accelerates at a constant rate for 400 m. Find the velocity at the end of the race.

    so Vo=0m/s
    acceleration is constant
    and we need to find Vf

    2. Relevant equations
    Ff = muN
    Velocity and acceleration:
    Constant acceleration:
    v = v0 +at
    x = x0 +v0t + 1/2at^2
    v^2 = vo^2 + 2ax

    3. The attempt at a solution
    Personally, I don't know how to approach this. If the mass, acceleration, or time were given I would be able to do this, but since they are not, I'm thoroughly stumped.
  2. jcsd
  3. Jan 18, 2010 #2
    I think the point is that since its a race, the car is accelerating as much as possible given the coefficient of friction. Do you agree with that? If so, use that to solve for the acceleration and you are home free.
  4. Jan 18, 2010 #3


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    Science Advisor
    Homework Helper

    Welcome to PF!

    Hi aamir23! Welcome to PF! :smile:

    (have a mu: µ and try using the X2 and X2 tags just above the Reply box :wink:)

    Yes, I think Phyisab**** :smile: is right …

    sometimes, you have to read the question very carefully, and then make an intelligent guess as to what's going through the examiner's mind! :rolleyes:
  5. Jan 18, 2010 #4
    sweet. i just got it. Thanks a ton.
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