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Homework Help: Newton's second law

  1. Oct 2, 2008 #1
    1. The problem statement, all variables and given/known data

    A 50,000 kg locomotive is traveling at 60.0 when its engine and brakes both fail.

    How far will the locomotive roll before it comes to a stop?

    I'm completely lost and i dont know how to get started on this question
  2. jcsd
  3. Oct 2, 2008 #2


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    F = m*a

    If there is no braking, there is no force. No force means no deceleration.

    Is that the entire statement of the problem?
  4. Oct 2, 2008 #3
    yes thats the entire question
  5. Oct 2, 2008 #4
    for F=m*a there is no acceleration because its alrdy travelling at 60m/s sorry i left that "m/s" out of the question
  6. Oct 2, 2008 #5


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    Better hope there is a lot of track then.
  7. Oct 2, 2008 #6
    If the problem doesn't state a friction force involved, or any other type of force involved, then the train will keep moving until...some force interact with it.
  8. Oct 3, 2008 #7


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    Re: newton's FIRST law

    Yup! :biggrin:

    btw, this isn't a Newton's second law problem, but a Newtons first law problem …

    a body on which no forces act continues to move with uniform velocity. :wink:
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