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Homework Help: Very tricky question

  1. Sep 23, 2010 #1
    Very tricky question!!!!

    Help me try to figure out this problem please!! :(

    I was driving along at 21 m/s , trying to change a CD and not watching where I was going. When I looked up, I found myself 44 m from a railroad crossing. And wouldn't you know it, a train moving at 29 m/s was only 56 m from the crossing. In a split second, I realized that the train was going to beat me to the crossing and that I didn't have enough distance to stop. My only hope was to accelerate enough to cross the tracks before the train arrived. If my reaction time before starting to accelerate was 0.42 s , what minimum acceleration did my car need for me to be here today writing these words?
    THANKS
     
  2. jcsd
  3. Sep 23, 2010 #2
    Re: Very tricky question!!!!

    What was your attempt to the question?
     
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