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Homework Help: Calculating distance with vehicle at constant velocity, & vehicle with acceleration=4

  1. Feb 3, 2010 #1

    Ax3

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    1. The problem statement, all variables and given/known data
    "A speeding motorbike travels past a stationary police car at a speed of 35ms-1. The police car starts accelerating immediately at 4ms-2, and keeps accelerating at this rate until it has passed the bike.

    - How far has does the police car travel before it overtakes the motorbike? (Ans=613m)
    - At what time does the police car overtake the motorbike? (Ans=17.5s)

    3. The attempt at a solution

    I have tried using a suvat equation, namely v=u+at to calculate the time taken for the police car to catch up to the motorbike (where i use v=35), however obviously the police car will never catch up to the bike if it only matches its velocity.. I'm really unsure of what to do next because trial and error using suvat equations has not provided me with much assistance.

    Thanks in advance for any help! (Im just after some clarification as the steps i would need to take/variables i would need to identify in order to answer a question similar to this)
     
  2. jcsd
  3. Feb 3, 2010 #2

    radou

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    Homework Helper

    Re: Calculating distance with vehicle at constant velocity, & vehicle with accelerati

    Hint: write down the expression for the distance traveled by both vehicles.
     
  4. Feb 4, 2010 #3

    Ax3

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    Re: Calculating distance with vehicle at constant velocity, & vehicle with accelerati

    Thanks heaps radou! i figured it out
     
    Last edited: Feb 4, 2010
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