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Homework Help: Hi guys

  1. Oct 14, 2012 #1
    Yeah I cannot figure this out...

    1. The problem statement, all variables and given/known data

    .A cannon fires a cannonball 500.0m downrange when set at a 45.0o angle. At what velocity does the cannonball leaves the cannon?

    Given Angle : 45
    Distance: 500m
    Vi : ?

    2. Relevant equations

    dy = viy(t)+ 4.9(t)^2

    3. The attempt at a solution

    Only thing I figured out is that vix = viy

    and that t = 500/vicos45
    Last edited: Oct 14, 2012
  2. jcsd
  3. Oct 14, 2012 #2
    so if you know how long it was in the air, how long did it take the cannonball to get to its max height

    if you know how long it took to get to the max height, then you can get the initial velocity in the y direction from that
  4. Oct 14, 2012 #3
    I think time is irreleavent here...
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