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Freely Falling Object

  1. Oct 6, 2009 #1
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution

    A freely falling object requires 1.10 s to travel the last 20.0 m before it hits the ground. From what height above the ground did it fall? (Ans. in m.)

    I am completely lost on modeling this problem. Please help me figure it out.
  2. jcsd
  3. Oct 6, 2009 #2


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    Homework Helper

    The model is just accelerated motion so you have the usual
    V = Vi + at and d = Vi*t + .5*a*t^2 to work with.
    Looks like you don't have enough info to use the first one, but the second one can be used to get the Vi - the velocity at height 20 m.
    That's a good start. Then you can use the first equation to found out when the velocity was zero.
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