Recent content by coldcell

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    Optimization height and radius problems

    V = 2/3 pi r³ h 200 = 2/3 pi r³ h 300 = pi r³ h h = 300/ (pi)(r³) So this is the relationship that I find between height and radius. This is where I'm lost. The pricing of the cynlindrical wall and the hemisphere :S If I can get the formula for this one, I think I can solve the problem/...
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    Finding ways from A to B in 3d objects

    Ah yes I see it... but is it that simple? We are assuming if we go to the right, it's 1 way. But we have in fact, crossed 2 boxes. To be honest, I don't really understand the question myself :S
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    Finding ways from A to B in 3d objects

    Find the total number of ways to go from A to B, if each way is the shortest route. http://img151.imageshack.us/img151/9875/010hr.jpg This is a rough sketch of 2 by 2 by 2 object. I have to find the number of ways for x by x by x object and x by y by z object. I tried doing it for...
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    Ordering Dozen Doughnuts: How Many Ways?

    Darn I should have thought about grouping the donuts together... how dumb am I :( So it's simply 16 C 4, or 16!/(4!12!) since there are 16 items, 4 alike, 12 alike. That hint is REALLY big. THANKS!
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    Ordering Dozen Doughnuts: How Many Ways?

    The doughnut shop has 5 kinds of doughnuts: a, b, c,d and e. There are unlimited supply of each kind. In how many ways can you order a dozen doughnuts? Well, my first instict is to simply 5^12. But then I realize aaaab is the same as baaaa... hence the order doesn't matter. I'm trying...
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    Arrangement Problem Solutions: 10 Trees

    Just read the guide-lines :S. Actually I'm in Grade 12 and since I took Calculus last semester, I thought these questions are appropriate in this forum. Where should I have put it? 1. I tried many things, but the closest answer I can get is 900. Since the trees of each kind are the same, we...
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    Arrangement Problem Solutions: 10 Trees

    1. Ten trees - four pines, four cedars, and two spruce- are planted in two parallel rows of five trees. How many arrangements are possible if each row must have the same composition of trees, not necessarily in the same order. 2. Suppose we want to creat subsets of the ten digits {0, 1, 2...
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    Understanding the Energy Conservation Principle in Roller Coaster Physics

    Hm... let me see if I get this right: Total energy to bring the train to the top = mgh That's it right? As for the second question, I'm still confused. I realize that the friction is causing energy loss.. but how do calculate the friction when you don't know the friction constant?
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    Understanding the Energy Conservation Principle in Roller Coaster Physics

    I'm not sure if this question belongs to this forum or advanced phsyics.. but since I'm still in high school, I think this is the right forum. I'm doing physics questions based on roller coaster and am just a little bit confused on how to answer some questions. You know : Mass of each...
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