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Homework Help: 1 Dimensional Kinematics

  1. Jan 28, 2009 #1
    Hi Guys! I'm having trouble with 2 problems that I only have 1 attempt left to answer correctly so if someone could please just tell me step by step how to complete them that would be great. Thanks to those who help.

    Problem 1: A sports car moving at constant speed travels 115 m in 5.3 s. If it then brakes and comes to a stop in 4.0 s, what is its acceleration? Express the answer in terms of g's, where g = 9.80 m/s2. (Take the positive direction to be the direction of travel.)

    Problem 2:A rock is dropped from a sea cliff and the sound of it striking the ocean is heard 4.2 s later. If the speed of sound is 340 m/s, how high is the cliff?

    Again, thanks a lot.

  2. jcsd
  3. Jan 28, 2009 #2


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    Homework Helper

    What have you tried so far?

    In the first one how fast was the car going? You need that to figure out how fast it decelerates.

    What about the second one?
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