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Homework Help: Simple Projectile Motion of ball

  1. Feb 12, 2006 #1
    Can someone tell me what I'm doing wrong here:

    A ball is thrown horizontally from the roof of a building 58 m tall and lands 35 m from the base. What was the ball's initial speed?

    X0= 0m Y0= 0m
    X= 58 m Y= 35 m
    Vx=? Vy=0 m/s
    Ax=0 m/s/s Ax=-9.8 m/s/s
    T=?

    35=0+0T-.5(-9.8)T^2
    T=2.6 s

    58=0+Vx(2.6)
    Vx= 22 m/s <----------I know this is wrong
     
  2. jcsd
  3. Feb 12, 2006 #2

    HallsofIvy

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    Science Advisor

    You've got your distances reversed! The building is 58m tall- that's the vertical distance: Y= 58m. The ball went 35 m horizontally: X= 35m
     
  4. Feb 13, 2006 #3
    Thanks! I should have known it was something like that after cheking my math so any times
     
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