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Bicycle down hill

  1. Apr 9, 2006 #1

    daniel_i_l

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    I noticed that if two bicycles roll down a hill, then the one with bigger wheels will get to the bottom first (I tested this with my brother). I could only think of one explanation: The bigger wheels make less revolutions and thus have less friction. Is that the reason? Are there other ones?
    Thanks.
     
  2. jcsd
  3. Apr 9, 2006 #2

    Kurdt

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    Differing wheels do make a difference as the energy goes into rotation aswell as movement. E(translation)=1/2mv^2 + E(rotation) = 1/2 I w^2. Where w= 'omega' = angular velocity. I is the moment of inertia which depends on the structure of the wheel.
     
  4. Apr 9, 2006 #3

    daniel_i_l

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    But that would mean that a bigger wheel would roll down more slowly.
     
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