Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: One Dimensional Kinematics of Object

  1. Sep 10, 2008 #1
    1. The problem statement, all variables and given/known data
    An object is released from rest at a height h. It travels 0.31h during the first second of its descent. Determine the average velocity of the object during its entire descent.

    2. Relevant equations

    X - Xo = Vot + .5at^2
    v^2 = Vo^2 + 2a(X - Xo)
    X - Xo = .5(Vo + V)t

    3. The attempt at a solution
    I basically have no idea where to start.
    .31/1 = .31 m/s is the velocity in the first second, but that is not the initial velocity, which is 0.
    h = .5(0+Vf)t = .5Vf*t, but I have no idea how one would get a numerical answer, which is what I need.
  2. jcsd
  3. Sep 10, 2008 #2


    User Avatar
    Gold Member

    Perhaps try figuring out what the height actually is to begin with. How far does any object fall under the influence of gravity in 1 second? You are told that this distance is 31% of the total distance, so to what height was it raised? See if you can work from there.
  4. Sep 10, 2008 #3
    I love you.
    Sorry for being an idiot, that's what always gets me.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook