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Homework Help: Trajectory Problem: Shooting a cannon

  1. Oct 11, 2011 #1
    1. The problem statement, all variables and given/known data
    A pirate ship is on a waterfall above a fort. The height of the waterfall is 200m above the fort. The pirate captain fires a cannon with an initial velocity 40m/s at angle of 40 degrees. If the cannonball makes a direct hit on the fort, how far away(horizontally) was the pirate ship when it fired.


    2. Relevant equations
    First find x and y comp.
    40cos45=28.28m/s
    40sin45=28.28m/s

    final velocity^2 = initial velocity^2 +2ad
    Final velocity^2= (40^2) + 2(-9.8)(-200)
    final velocity= 74.3m/s

    final velocity= initial velocity + at
    74.3m/s= 40m/s+(-9.8)t
    t= 3.5s

    Velocity(x-direction) x t= horizontal distance
    28.23 x 3.5s = 98.98m



    3. The attempt at a solution

    98.98m
     
  2. jcsd
  3. Oct 11, 2011 #2
    I want to know if i correctly solved the problem.
     
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