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Homework Help: Finding lap time

  1. Sep 16, 2012 #1
    1. The problem statement, all variables and given/known data

    Friction=0.8
    r=50 m
    T=?

    2. Relevant equations

    T=distance/speed

    Perimeter=2*pi*r

    Fc=(mv^2)/r

    Ffriction=m*g*friction

    3. The attempt at a solution

    Perimeter
    2*3.14*50=314

    Fc=Ffriction

    (mv^2)/r=m*g*friction

    v=r*g*friction

    = 50*9.82*0.8=391.8

    T=314/391.8 = 0.8 s

    Is this correct? Seems a bit wrong to me :S
     
    Last edited: Sep 16, 2012
  2. jcsd
  3. Sep 16, 2012 #2
    forgot to take the square root of velocity.
     
  4. Sep 16, 2012 #3
    Ah! That gives me almost 16 sec, which makes more sense

    Thank you!
     
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