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Homework Help: Roller coaster problem

  1. Nov 6, 2005 #1
    Roller coaster Vel. Initial=10m/s, Height initial=100m, and the mass of the coaster is 1000kg all at the starting point (*).
    Have to find the speed of coaster at point A, point A's height is the same as the starting points, b is 1/2 of a's height, c's height is zero.
    Coaster kinda looks like: * is starting point

    ..................................................../
    ......._*_.........._A_......................../
    ....../----\......./---\......_B_.........../
    ...../------\__/-----\__/----\......../
    __/-------------------------\_c_/


    I found Vf of the starting point with vf^2=vo^2+2 a deltaH
    and used that Vel for Vo when i do it again but for point h.
    what should I do?, my Vf of the starting point i got was 45.4m/s :yuck:
     
  2. jcsd
  3. Nov 6, 2005 #2
    vf^2 = vo^2+ 2*a*(xi-xf)

    Vo = 10 each time
    a = 9.81 each time
    xi = 100 each time
    xf = height above ground

    this should work
     
  4. Nov 6, 2005 #3

    kp

    User Avatar

    what about conservation of energy?
     
  5. Nov 6, 2005 #4

    lightgrav

    User Avatar
    Homework Helper

    I hope ViewtifulBeau realizes that that equation
    comes from (as a special case) Energy conservation.

    I DO wish you folks would stop treating "g" as an acceleration!
     
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