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Horizontal and Vertical Velocity

  1. Sep 23, 2012 #1
    A rookie quarterback throws a football with an initial upward velocity component of 16.5 and a horizontal velocity component of 18.3 . Ignore air resistance.

    A)How much time is required for the football to reach the highest point of the trajectory?

    I got 1.68s which is correct

    B) How high is this point?

    I can't get the right answer. I got 16.9m by doing: 0m+18.3(1.68)+1/2(-9.8)(1.68)2

    Help please!
  2. jcsd
  3. Sep 23, 2012 #2
    b) To determine the max height of the projectile, you only need to use the vertical components. You incorrectly used the horizontal component for the displacement formula. It should be...

    s = 16.5(1.68) + ½(-9.8)(1.68)²
  4. Sep 23, 2012 #3
    Thank you!
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