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Homework Help: A cyclist moving on a level road

  1. Aug 25, 2012 #1
    1. The problem statement, all variables and given/known data

    a cyclist is moving on a level road at 4m/s stops pedaling and lets the wheels comes to rest the retardation of cycle has 2 components a constant 0.08m/s^2 due to friction in working parts and resistance of 0.02v^2/m where v is speed in m/s and distance tranversed by the cycle before it comes to rest.(log 5=1.6)

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Aug 25, 2012 #2


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    You understand that this is a differential equation right. You need to write an equation in the form:

    [tex]\frac{dv}{dt} = -f(v)[/tex]
    Are you able to write this equation? This is your starting point.

    BTW. f(v) here is the total retardation as a function of velocity.
  4. Aug 26, 2012 #3
    yes after that i do not know what to do
  5. Aug 26, 2012 #4


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    Rewrite it as:

    [tex]\frac{dt}{dv} = \frac{-1}{f(v)}[/tex]

    and integrate.
  6. Aug 26, 2012 #5

    Ray Vickson

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    Are you saying you do not know how to solve a differential equation?

  7. Aug 26, 2012 #6


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    Per the forum rules, you need to show more effort to receive help here.
  8. Sep 21, 2012 #7
    finally got it thanks
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