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Homework Help: PLEASE Can any one solve this problem

  1. Aug 17, 2008 #1
    A body dropped from a tower travels half of the total distance in the last second of its motion
    .The total time taken of will be ...?
    take g = 10 m/s^2

    choices

    a) square root 2 secs

    b) 2 secs

    c) 2+square root 2 secs

    d) 2*square root 2 secs
     
  2. jcsd
  3. Aug 17, 2008 #2
    Do you know your basic kinematics formulas?
     
  4. Aug 18, 2008 #3

    dynamicsolo

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    Homework Helper

    You will need to write down the formula for the distance an object falls under gravity in a time t, in the absence of air resistance. You then need to make a comparison between

    the distance 2D that the object falls in T seconds

    and

    the distance D that the object falls in 1 second .

    You do not need to know the actual height of the tower, which we've called 2D, since you will be substituted for D using your second equation. This will give you enough information to solve for T, the total time of the fall. (You'll also find that we don't actually care what value g has...)
     
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