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Homework Help: Physics chase problem help

  1. Sep 9, 2012 #1
    Physics chase problem help!!

    Hi, i'm having a lot of difficulty with my physics homework. I'd really appriciate it if someone would help me out here :D

    1. The problem statement, all variables and given/known data
    Karan is driving at 90 km/h on a straight road at night, when she sees a skunk cross the road 60.0m ahead of this car. It takes him 0.25s to react before he puts on the brakes and decelerates at -5.00m/s2. Meanwhile, the skunk obliviously walks across the 5.00m wide road at 0.70 m/s. Calculate whether
    a) Karan stops in time before she hits the skunk
    b) the skunk crosses the road before Karan get there; or
    c) Karan squishes the skunk

    2. Relevant equations
    I've just been given basic kinematics equations.
    With variables v, d, t, a

    3. The attempt at a solution
    I'm not sure how to start answering this question.
  2. jcsd
  3. Sep 9, 2012 #2
    Re: Physics chase problem help!!

    The obvious first step is to convert all into SI system i.e km/hr to m/s..etc

    from here there is a 2 way approach..

    go with karan or skunk

    for karan...

    find time taken to reach at 60meter from origin
    then use time to find whether the skunk manages to crosses
    if skunk just reaches then it is crushed
    if skunk dosent reach then karan is faster
    if skunk reaches and travels more then it reaches faster

    for skunk...

    find time taken to cross the road
    then compute whether karan travels less than 60 m or more in given time

    if more then karan crosses first
    if less then skunk passes first
    if equal then god save the skunk

    here it is assumed that karan travels along opp edge of 5.00 m wide road from where skunk starts walking

    hope it helps
  4. Sep 9, 2012 #3
    Re: Physics chase problem help!!

    Thanks a lot it did help managed to solve the question :D I'm not sure if its right but yea!!
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