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Homework Help: Riding a bicycle

  1. Oct 23, 2007 #1
    1. The problem statement, all variables and given/known data

    A boy is riding a bicycle on a straight, level and smooth road. There is no wind. He accelerates to 15m/s, and then suddenly stops pedaling. What will happen?

    a) immediately begins to slow because of inertia
    b) slows because of inertia, but not immediately
    c) slows because of his mass (with force = 0)
    d) continues moving because of inertia
    e) continues moving because the pedaling force persists

    2. Relevant equations

    (Law of inertia)

    3. The attempt at a solution

    I know that the answer is either a or b. I believe that he will immediately slow, so I am leaning towards a. Can someone help please?
  2. jcsd
  3. Oct 23, 2007 #2


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    I don't like the way this question is worded. But, what happens to objects when there is no force acting on them?
  4. Oct 23, 2007 #3
    The wording is somewhat vague.
    As we are both guessing, "straight, level and smooth road" likely equates to frictionless surface, otherwise the question would not have mentioned what type of road it was. A road is a road, unless it is frictionless.
  5. Oct 23, 2007 #4
    So therefore it is a frictionless surface and the bike would not slow down. Correct?
  6. Oct 23, 2007 #5


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    Yes you are correct.
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