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Homework Help: Shooting At Moving target

  1. Oct 8, 2008 #1
    1. The problem statement, all variables and given/known data
    Person A is shot out of cannon at 100m/s at 30 degrees above the horizontal on top of a 75 meter tall cliff. After 3 seconds, Person B, standing next to the cannon, shoots an arrow at 200m/s at Person A. At what height does the arrow strike person A, and what angle did he fire at?

    2. Relevant equations
    X_Ay=75+200 sin⁡(θ) (t-3)+g/2 〖(t-3)〗^2
    X_Ax=200 cos⁡(θ) (t-3)
    X_By=75+50t+g/2 t^2
    X_By=86.6t

    3. The attempt at a solution
    {(75+200sin(θ)(t-3)+g/2(t-3)^2)^2 + (200cos(θ)(t-3))^2}^1/2 = {(75+50t+g/2 t^2)^2 + (86.6t)^2}^1/2

    For some reason I am unable to isolate theta
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Oct 8, 2008 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Make use of the fact that A and B must have the x and y coordinates when they collide.
     
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