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Homework Help: Equations Help Please

  1. Dec 5, 2004 #1
    I am having some problems with equations for a problem. The problem isnt really a question, it's more of finding equations to make something work. Basically, It is a graph on Microsoft Excel, that resembles a 2D track. The track has variable points that you can change, to increase height, distance, Coefficient of Friction, Centripetal Acceleration, Force Centripetal, etc. I have some equations figured out, but I am stuck on a few. Here is what i have and what i need, any help is appreciated. (remember there are no numbers, just equations)

    The first is IE ( Initial Energy ) without Centripetal Acceleration added. I have no idea where to even start with this equation, but i assume that Initial Energy is the greatest kinetic Energy, minus the Kinetic Energy at the point you are? I need alot of help there. Final Equation: TE - KE

    The second is IE of Individual Track segment with Centripetal Acceleration added. For this, I assume that it is once again the Total Energy minus the Kinetic Energy at that point plus ( Velocity^2 / Radius ) I dont know exactly how to get the radius though ( is it half of the track segment?? :confused: ) Final Equation: TE - KE + [v^2/(1/2)(TrackSegmentLength)]

    The third is Speed with Centripetal Acceleration. For this I think I have it, but since i have Kinetic Energy as a Given, I would use the Equation v=SquareRoot(KE/.5m)

    The fourth is Distance Traveled, for this, wouldnt it be the new track segment plus all of the previous track segments?? :confused: Final Equation: New Track + All Previous Track

    That is all i have, please correct me on equations if I'm wrong, or if you need clarification id be glad to give it to you.
  2. jcsd
  3. Dec 5, 2004 #2
    What do u mean by centripetal acceleration added? when the centripetal acceleration is added, it shouldnt change the speed and only change the direction? no?
    Last edited by a moderator: Dec 5, 2004
  4. Dec 5, 2004 #3
    yes, Think of a track that goes up and down at random points...thats what its saying...so what is the speed with Centripetal acceleration added..I am still very confused..because none of my equations are working :confused: :cry:
  5. Dec 5, 2004 #4
    the speed should still be the same as the initial speed.
  6. Dec 5, 2004 #5
    But what about Initial energy and speed? how do I get them without having Total Energy?
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