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Homework Help: Lost on Projectile motion problem

  1. Sep 27, 2010 #1
    1. The problem statement, all variables and given/known data

    A marble is thrown horizontally with a speed of 12.0 m/s from the top of a building. When it strikes the ground, the marble has a velocity that makes an angle of 30.3 ° with the horizontal. From what height above the ground was the marble thrown?

    -im lost at where to begin

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Sep 27, 2010 #2
    I think the key in this question is whether or not you are ignoring air resistance?

  4. Sep 27, 2010 #3
    yes, while ignoring the air resistance
  5. Sep 27, 2010 #4
    If there is no air resistance, there is nothing acting to decelerate the ball in the horizontal plane. The balls horizontal velocity is a constant 12m/s.
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