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Homework Help: 2d kinematics problem

  1. Oct 31, 2011 #1
    1. The problem statement, all variables and given/known data

    So...In Central Oregon there is a winter time problem that is troublesome to gardeners having to do with large masses of snow sliding off the roof and crushing plants and shrubs on the ground. Physics (in particular 2-D Kinematics) allows us to determine some features of the vegetative danger zone. We'll assume for the purposes of this activity that the roof is a typical 4 in 12 pitch (meaning it rises 40 cm and it goes inwards 120 cm ) and experiments have shown that when large amounts of snow slide off they leave the edge of the roof at 2.4 m/s. The edge of the roof is 3.3 m above the ground and 40 cm outward from the wall of the house.

    2. Relevant equations

    3. The attempt at a solution
    I honelsty don't even know where to begin. Our teacher likes to gives us scenerios and for us to figure out possible questions that he might ask depending on the scenerio. If someone could give me a jumping off point or anything would be helpful. attached is the scenerio in picture form.

    Attached Files:

  2. jcsd
  3. Oct 31, 2011 #2


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    Well, it looks to me like the question is, "How far from the house will the snow hit the ground?" You are given the speed at which the snow comes off the house, and the angle at which it comes off. You can calculate the horizontal and vertical components of the initial speed from that, then use the equations of motion, with no acceleration horizontally and the acceleration due to gravity vertically, to find the time and distance from the house at which the snow hits the ground.
  4. Oct 31, 2011 #3
    thanks for the quick reply but besides the 90 degree angle, could you tell me what other angles were given. Becuaese i can't see them.
  5. Oct 31, 2011 #4
    So i did some work, i just don't know where to go from here or really what angle i am supposed to use, please help

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