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Homework Help: Collision question

  1. Oct 11, 2008 #1
    collision question!!!

    Speedy Sue, driving at 32.0 m/s, enters a one-lane tunnel. She then observes a slow-moving van 160 m ahead traveling with velocity 5.20 m/s. Sue applies her brakes but can accelerate only at -2.00 m/s2 because the road is wet. Will there be a collision?

    If yes, determine how far into the tunnel and at what time the collision occurs. If no, determine the distance of closest approach between Sue's car and the van and enter zero for the time.

    i already know there will be a collision
    but im not sure how to calculate how far into the tunnel it will happen

    im guessin to use the final position function..but i dunno
  2. jcsd
  3. Oct 11, 2008 #2


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    Re: collision question!!!

    If Sue starts braking immediately after entering the tunnel, how far into the tunnel will she have come to a stop?
    How long will it take her to brake? What is then the distance the van has travelled?
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