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Homework Help: Please help fast

  1. Sep 18, 2008 #1
    I need help solving this problem, if you could provide a solution i would greatly appreciate it

    1. The problem statement, all variables and given/known data
    An elevator accelerates from the ground with a uniform acceleration 'a.' After 4.0 seconda, an object is dropped out an opening in the floor of the elevator and that object hits the ground 4.5 seconds later.

    a) what is the value of the acceleration 'a?'

    b) How high was the elevator when the object was dropped?

    c) What is the speed of the object when it hits the ground?

    2. Relevant equations
    X=Xo+Vot+1/2(a)(t^2 )
  2. jcsd
  3. Sep 18, 2008 #2


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    Hi joeth04! :smile:

    Only way to solve this is to start "Let the acceleration be a", and then work out how the height and the velocity after 4.0 seconds depend on a, and then work out how long it takes the object to hit the ground, and then put that equal to 4.5.

    Have a go! :smile:
  4. Sep 18, 2008 #3


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