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Homework Help: Gr 11 Roller Coaster Contest

  1. Dec 29, 2004 #1
    I'm a gr 11 physics student at Ashbury College (Ottawa, Canada) and our class (in multiple teams) has been entered in a roller coaster contest, held by Wonderland. (A theme park in Ontario, Canada).

    My friends and I are determined to win this contest, and I am sure that the ideas of those in this forum will assist us greatly.

    As the contest rules are on a webpage, I am not going to type them all out, rather I will provide the link: :tongue2:


    As we can only participate in one area of the contest, and neither my friends or I are art students, we decided to compete in the technical merit field.

    We are hoping we can obtain a score of over 60 Million points. :bugeye:

    Any ideas welcome, when I find a scanner I'll post our initial design, as well as the point calculation we did for it.

    Thanks in advance,
    Last edited by a moderator: Apr 21, 2017
  2. jcsd
  3. Dec 29, 2004 #2
    Just thought I'd add a couple questions to start us off...

    1. Obviously, because points are awarded for loops, the greater the velocity throughout the course the better. Say I had 2 marble's, 1.3 cm and 2.5cm. Which would be better to use? Why?

    2. I was thinking of reducing friction on the course, perhaps by using ball bearing grease to lubricate the track...is this a good idea?

    3. What material should we use for the track?

    4. The contest guidelines state that we must have 2 horizontal 360 degree turns, where is the best spot to put these? They would be very shallow so as to not take up a great deal of space and thus maximize the gravitational potential energy of the marble.

  4. Dec 29, 2004 #3


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    You should definitely find out how the 'loop diameter' is calculated for non-circular and helical (or helix-like) loops.
  5. Dec 29, 2004 #4
    Last edited by a moderator: Apr 21, 2017
  6. Dec 29, 2004 #5
    (f) Vertical Loop Diameter score calculation:

    Determine the total diameter score of each of the vertical loops. For loops that are not circular record the diameter at the LARGEST spot. The coaster ride must have at least one vertical loop. If the vertical loop is open at the top of the loop (so that the steel ball or marble would fall out if it was moving too slowly) on the inner side then the diameter that is counted should be multiplied by 1.5. To be considered a vertical loop the angle of the loop with respect to the vertical must be less than 20° (otherwise it is considered a horizontal turn).

    A corkscrew is a special case type of a vertical loop. Each complete revolution of 360° will count as one complete vertical loop. These will be recorded to the nearest 1/4 of a loop.

    (h) The velocity of the ball must be changing (in either magnitude &/or direction) for the entire trip. Coasters will be eliminated if the velocity remains constant for more that two seconds (this means the track should not be straight and level for more that 2 seconds of travel). *** this is a new regulation to prevent straight horizontal tracks***

    (g) One final note: The coasters are judged in an outdoor environment and wind and cold weather conditions sometimes exist. This is a difficult factor for you to consider when building your coaster but you should be aware of it.

    Sorry NateTG, the new link explains the calculations. Above in blue is waht it says regarding non-circular loops.
  7. Jan 4, 2005 #6


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    Regarding marbles: You're probably going to be best off with the most massive marble you can get. I doubt that you'll be doing a whole lot of special work to construct your own marbles, so you won't need to worry about hollow ones or anything similar.

    Regarding track construction: You'll want the track to be as stiff as possible. Any section of track that wiggles due to the passing of the ball will slow you down. Since the goal is to get as many large loops as possible, you want to conserve as much energy as possible.

    Regarding lubricants: Placing oil or grease on the track is likely to slow the ball down instead of speeding it up. You might consider testing various lubricants with an inclined straight section of track and coming to your own conclusions. You may have good results with more solid lubricants such as wax or graphite.

    If there is only access to straight and circular sections of track the simplest design would probably be a slow, almost flat, windy section followed by,a more or less straight drop followed by a helix of loops. (This is very similar to the winning previous coaster linked to from the rules page.)

    After some thought, and looking at the winning design, it occurs to me that it would be closer to ideal to have an inclined row of loops with short sections of inclined straight track between them (think of a tilted board with a straight looping track on it, or a tilted corkscrew). You should then also be able to 'mass produce' these repeated straight sections and loops rather than custom building the entire track. You could build it on a level board, and then fix the board into place for easier construction as well. Alternatively, a corkscrew could be constructed out of a section of pipe using a lathe.

    A figure-eight at the end will allow you to meet the technical requirement of two 360 degree turns.
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