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Homework Help: Roller coaster physics problem!

  1. Dec 8, 2012 #1
    1. A diagram of a roller coaster is given. In the diagram, there are 3 humps in the track. At the top of the first hump(point A) the height is 60m from the ground. Point B is at the bottom of point A and is 5m below the ground. (height from point A to B is -65m). From point B to point C is 64m. From point C to D is -67m. From point D to E is 71m.
    The coaster is at rest at point A.
    Vy = final velocity
    Vx = initial velocity
    g = acceleration due to gravity (-9.8m/s)
    hxy = the difference in height from point x to point y

    2. Vy2 = Vx2 + 2ghxy

    3. The first question is to find the velocity of the coaster at point B.
    Vy2 = 0 + 2(-9.8)(-65)xy
    Vy2 = 1274
    √Vy2 = √1274
    Vy = 35.69m/s

    all i really need is a confirmation of my answer. I don't know why but i think i might be wrong.
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Dec 8, 2012 #2


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    Homework Helper

    Yes that would be correct.

    Also in your final equation, what you are essentially doing is equation KE and PE at the various points.
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