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Amusment park for physics class

  1. May 12, 2004 #1
    Went to an amusment park yesterday for physics class. Went on a ride called the "hellevator" where you sit down and it shoots up a certain distance then lets you free fall. My question is if the acceleration upwards occurs in the first 5 meters how do you figure out that acceleration?
  2. jcsd
  3. May 12, 2004 #2
    Acceleration=change in velocity/time.
    So, All you need to know is how fast you were going in the first five meters, and how long it took you to reach your final velocity.

    Punch in the numbers and whalla! !Y voy!

    Paden Roder
    Last edited: May 12, 2004
  4. May 12, 2004 #3
    lol k i think i got it. Thx :biggrin:
    Last edited: May 12, 2004
  5. May 13, 2004 #4


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    I think the real problem involves figuring out the acceleration using the maximum height reached, H. You'll find that (the acceleration),
    a = g*(H-5)/5, where g = 9.8 m/s^2.
    Last edited: May 13, 2004
  6. May 13, 2004 #5

    To find the acceleration for the first five metres, we need to know the velocity at the end of that upward acceleration. Two parts to the trip: the first five metres, and the rest of the distance up. If max height attained from take off is H, then, for the second part of the trip:

    v (initial) = what we need to find out
    v (final) = zero (at max height)
    a = 9.8 m/s^2 [down] (if friction and air resistance can be ignored, only gravity acts)
    d = (H-5) [up]

    solve for v (initial) using vf^2 - vi^2 = 2ad

    The v (initial) you just discovered is the v (final) for the 5 metres of acceleration at the beginning. You now use:

    v (initial) = zero
    v (final) = v (initial) from calculation above
    d = 5.0 m [up]

    and solve for acceleration using

    vf^2 - vi^2 = 2ad

    Hope this helps.

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