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Homework Help: Simple 1-D Kinematics Question

  1. Aug 28, 2006 #1
    I tried this question multiple times, but now I've become stuck.

    A person shoots a gun straight up into the air on New Year's Eve. The velocity at which the bullet leaves is 3.00 x 10^2 m/s. What is the maximum altitude of the bullet?


    Here's what I've tried:

    I attempted to apply the x=1/2(vi+vf)t formula, but it's missing some variables, namely vf, t, and the displacement. I've also tried to find the final velocity through vf=vi+at, but then I'm missing the time. Then I tried to get the final velocity with vf^2=vi^2+2ax, but I'm now missing the displacement. I must be not seeing something very obvious here.

    EDIT: Ahh...gods. I have just realized something. vf = 0 when the bullet reaches the top. Silly me--that means it's not missing any variables.
     
    Last edited: Aug 28, 2006
  2. jcsd
  3. Aug 28, 2006 #2
    You're missing the displacement because that is what the problem is asking for. The displacement is the maximum height that the bullet reaches. Use that equation, with accleration being gravity.

    EDIT: OK!
     
    Last edited: Aug 28, 2006
  4. Aug 28, 2006 #3
    Heh, thanks for the help anyways. :)
     
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