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Dumb questioncan someone help me?

  1. Oct 16, 2005 #1
    Simple Projectile Question

    there is a volleyball net 2.24m high (the court is 9m by 9m on both sides), and you hit the ball while being 3m in the air, you are 8m away from the net, if the initial velocity is horizontal find
    A)what minimum velocity must the ball have to clear the top of the net
    B)what maximum velocity can it have if the ball is to strike the the back line on the other side of the net?
    V0 = ?
    X-X0 = 8m
    Y-Y0 = 0.76m
    (theta) = 84.57
    Vy2 = -2g(y-y0)
    Vy = 3.76m/s
    Vy = V0sin(theta) - gt
    Vy/-g = t
    t = 0.38
    X-X0 = V0x(t)
    8m = V0x(0.38s)
    V0x = 21.05 m/s???not likely
    Last edited: Oct 16, 2005
  2. jcsd
  3. Oct 17, 2005 #2

    Tom Mattson

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    Staff Emeritus
    Science Advisor
    Gold Member

    I haven't run through the numbers, but your procedure looks good for part a.

    You need to do something similar for part b. Just as in part a when you asked yourself what must [itex]V_{0x}[/itex] be in order to clear the net, now you have to ask yourself what must [itex]V_{0x}[/itex] be in order to not go past the edge of the court. The algebra is going to be the same, but with different numbers.
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