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Homework Help: Springs and motion of car

  1. Dec 8, 2006 #1
    1. The problem statement, all variables and given/known data
    A car towing a 92 kg trailor with a spring between the car and the trailor. the accelertion of the car is .3. the spring constant is 2300
    how far is the spring stretched


    2. Relevant equations
    Fs=kx


    3. The attempt at a solution

    Fs=kx
    ma=kx
    (92)(.3)=2300x
    x=.012m

    i am not sure if that was legal
     
  2. jcsd
  3. Dec 8, 2006 #2

    OlderDan

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    Science Advisor
    Homework Helper

    It is legal, but it rests on several assumptions.

    1) That the units of a are m/s²

    2) That the units of k are N/m

    3) That the acceleration of the trailor is constant- the length of the spring is constant. In reality, it would not be if the car started moving with constant acceleration at some point in time.
     
  4. Dec 8, 2006 #3
    thanks for the help
     
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