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How fast will the car be traveling at that instant?

  1. Aug 30, 2006 #1
    At the instant the traffic light turns green, an automobile starts with a constant acceleration a of 2.3 m/s2. At the same instant a truck, traveling with a constant speed of 9.6 m/s, overtakes and passes the automobile.
    (a) How far beyond the traffic signal will the automobile overtake the truck?

    (b) How fast will the car be traveling at that instant?

    Not exactly sure how to set the problem up. Like exactly how does the truck's speed help find the answer? I know I need to find the time it took to figure out the rest. I'm just missing something in the the question that will help set up the problem.
    Last edited: Aug 30, 2006
  2. jcsd
  3. Aug 30, 2006 #2
    You're looking for two equal distances where the time is also the same:

    scar = .5 * at2 = struck = vt
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