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Homework Help: More kinematics

  1. Jun 4, 2004 #1
    I'm sorry for posting so often, but I'm really stuck on these :cry:

    A cannon having a muzzle speed of 1000 m/s is used to destroy a target on a mountaintop. The target is 2000 from the cannon horizontally and hoom above the ground. At what anle, relative to the ground, should the cannon be fired (ignore air friction).

    I don'[t really know what to do with this either, except that the V0 in the x-direction is 1000 m/s and the V0 in the y-direction is 0 m/s and the acceleration in the y-direction is 9.81

    I don't really know where to go from here. any help would be super appreciated! :yuck:
  2. jcsd
  3. Jun 4, 2004 #2


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    Please remove the numerous typos here; I don't understand which parameters are present in this exercise :confused:
  4. Jun 4, 2004 #3


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    by making this assumption, you imply that the answer is 0 degrees. The problem only gives you the magnitude of the muzzle velocity I assume. This is a projectile motion problem, so all you have to do is break up the motion into the horizontal and vertical directions. In the horizontal direction, the velocity will be constant at [tex] V_o\cos \theta [/tex] , vertical magnitude for initial velocity will be [tex] V_o\sin \theta [/tex]. There is of course an acceleration of gravity vertically so take that into account as well with a kinematical relation. Then just solve for theta.
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